diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..d5b20d8
Binary files /dev/null and b/.DS_Store differ
diff --git a/ThirdSeminar/.gitignore b/ThirdSeminar/.gitignore
new file mode 100644
index 0000000..c2065bc
--- /dev/null
+++ b/ThirdSeminar/.gitignore
@@ -0,0 +1,37 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
diff --git a/ThirdSeminar/build.gradle b/ThirdSeminar/build.gradle
new file mode 100644
index 0000000..4ff82f2
--- /dev/null
+++ b/ThirdSeminar/build.gradle
@@ -0,0 +1,33 @@
+plugins {
+	id 'java'
+	id 'org.springframework.boot' version '2.7.11'
+	id 'io.spring.dependency-management' version '1.0.15.RELEASE'
+}
+
+group = 'sopt.org'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '11'
+
+configurations {
+	compileOnly {
+		extendsFrom annotationProcessor
+	}
+}
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
+	implementation 'mysql:mysql-connector-java:8.0.32'
+	implementation 'org.springframework.boot:spring-boot-starter-validation'
+	compileOnly 'org.projectlombok:lombok'
+	annotationProcessor 'org.projectlombok:lombok'
+	testImplementation 'org.springframework.boot:spring-boot-starter-test'
+}
+
+tasks.named('test') {
+	useJUnitPlatform()
+}
diff --git a/ThirdSeminar/gradle/wrapper/gradle-wrapper.properties b/ThirdSeminar/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..774fae8
--- /dev/null
+++ b/ThirdSeminar/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.6.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/ThirdSeminar/gradlew b/ThirdSeminar/gradlew
new file mode 100755
index 0000000..a69d9cb
--- /dev/null
+++ b/ThirdSeminar/gradlew
@@ -0,0 +1,240 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/ThirdSeminar/gradlew.bat b/ThirdSeminar/gradlew.bat
new file mode 100644
index 0000000..53a6b23
--- /dev/null
+++ b/ThirdSeminar/gradlew.bat
@@ -0,0 +1,91 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/ThirdSeminar/settings.gradle b/ThirdSeminar/settings.gradle
new file mode 100644
index 0000000..397b799
--- /dev/null
+++ b/ThirdSeminar/settings.gradle
@@ -0,0 +1 @@
+rootProject.name = 'ThirdSeminar'
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/ThirdSeminarApplication.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/ThirdSeminarApplication.java
new file mode 100644
index 0000000..e152738
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/ThirdSeminarApplication.java
@@ -0,0 +1,13 @@
+package sopt.org.ThirdSeminar;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class ThirdSeminarApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(ThirdSeminarApplication.class, args);
+	}
+
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/common/advice/ControllerExceptionAdvice.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/common/advice/ControllerExceptionAdvice.java
new file mode 100644
index 0000000..440ca10
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/common/advice/ControllerExceptionAdvice.java
@@ -0,0 +1,27 @@
+package sopt.org.ThirdSeminar.common.advice;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.MethodArgumentNotValidException;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.ResponseStatus;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+import sopt.org.ThirdSeminar.exception.ErrorStatus;
+import sopt.org.thirdSeminar.common.dto.ApiResponseDto;
+
+import javax.persistence.EntityNotFoundException;
+
+@RestControllerAdvice
+public class ControllerExceptionAdvice {
+
+    @ResponseStatus(HttpStatus.BAD_REQUEST)
+    @ExceptionHandler(MethodArgumentNotValidException.class)
+    protected ApiResponseDto handleMethodArgumentNotValidException(final MethodArgumentNotValidException e) {
+        return ApiResponseDto.error(ErrorStatus.VALIDATION_REQUEST_MISSING_EXCEPTION);
+    }
+
+    @ResponseStatus(HttpStatus.NOT_FOUND)
+    @ExceptionHandler(EntityNotFoundException.class)
+    protected ApiResponseDto handleEntityNotFoundException(final EntityNotFoundException e) {
+        return ApiResponseDto.error(ErrorStatus.NOT_FOUND_USER);
+    }
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/common/dto/ApiResponseDto.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/common/dto/ApiResponseDto.java
new file mode 100644
index 0000000..c3b45c1
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/common/dto/ApiResponseDto.java
@@ -0,0 +1,29 @@
+package sopt.org.thirdSeminar.common.dto;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpStatus;
+import sopt.org.ThirdSeminar.exception.ErrorStatus;
+import sopt.org.ThirdSeminar.exception.SuccessStatus;
+
+@Getter
+@RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+public class ApiResponseDto<T> {
+
+    private final int code;
+    private final String message;
+    private T data;
+
+    public static ApiResponseDto success(SuccessStatus successStatus){
+        return new ApiResponseDto<>(successStatus.getHttpStatus().value(),successStatus.getMessage());
+    }
+    public static <T> ApiResponseDto<T> success(SuccessStatus successStatus,T data){
+        return new ApiResponseDto<>(successStatus.getHttpStatus().value(),successStatus.getMessage(),data);
+    }
+    public static ApiResponseDto error(ErrorStatus errorStatus) {
+        return new ApiResponseDto<>(errorStatus.getHttpStatus().value(), errorStatus.getMessage());
+    }
+}
\ No newline at end of file
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/PostController.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/PostController.java
new file mode 100644
index 0000000..143c9b0
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/PostController.java
@@ -0,0 +1,33 @@
+package sopt.org.ThirdSeminar.controller;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+import sopt.org.ThirdSeminar.controller.dto.request.PostRequestDto;
+import sopt.org.ThirdSeminar.controller.dto.response.PostResponseDto;
+import sopt.org.ThirdSeminar.exception.SuccessStatus;
+import sopt.org.ThirdSeminar.service.PostService;
+import sopt.org.thirdSeminar.common.dto.ApiResponseDto;
+
+import javax.validation.Valid;
+import java.util.List;
+
+@RestController
+@RequiredArgsConstructor
+public class PostController {
+
+    private final PostService postService;
+
+    @PostMapping("/post/create")
+    public ApiResponseDto<PostResponseDto> crate(@RequestBody @Valid final PostRequestDto postRequestDto){
+        return ApiResponseDto.success(SuccessStatus.CREATE_SUCCESS, postService.create(postRequestDto));
+    }
+    @GetMapping("/post/{id}")
+    public ApiResponseDto<PostResponseDto> search(@PathVariable final Long id){
+        return ApiResponseDto.success(SuccessStatus.SEARCH_SUCCESS,postService.search(id));
+    }
+    @GetMapping("/post/search")
+    public ApiResponseDto<List<PostResponseDto>> searchByTitle(@RequestParam final String title){
+        return ApiResponseDto.success(SuccessStatus.SEARCH_SUCCESS,postService.searchByTitle(title));
+    }
+
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/UserController.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/UserController.java
new file mode 100644
index 0000000..0760451
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/UserController.java
@@ -0,0 +1,30 @@
+package sopt.org.ThirdSeminar.controller;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.*;
+import sopt.org.ThirdSeminar.controller.dto.request.UserRequestDto;
+import sopt.org.ThirdSeminar.controller.dto.response.UserResponseDto;
+import sopt.org.ThirdSeminar.exception.SuccessStatus;
+import sopt.org.ThirdSeminar.service.UserService;
+import sopt.org.thirdSeminar.common.dto.ApiResponseDto;
+import javax.validation.Valid;
+
+@RestController
+@RequiredArgsConstructor
+public class UserController {
+
+    private final UserService userService;
+
+    @PostMapping("/user/signup")
+    @ResponseStatus(HttpStatus.CREATED)
+    public ApiResponseDto<UserResponseDto> create(@RequestBody @Valid final UserRequestDto request){
+        return ApiResponseDto.success(SuccessStatus.SIGNUP_SUCCESS,userService.create(request));
+    }
+
+    @GetMapping("/user/{id}")
+    @ResponseStatus(HttpStatus.OK)
+    public ApiResponseDto<UserResponseDto> search(@PathVariable @Valid final Long id){
+        return ApiResponseDto.success(SuccessStatus.SEARCH_SUCCESS,userService.search(id));
+    }
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/request/PostRequestDto.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/request/PostRequestDto.java
new file mode 100644
index 0000000..093879c
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/request/PostRequestDto.java
@@ -0,0 +1,19 @@
+package sopt.org.ThirdSeminar.controller.dto.request;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+import javax.validation.constraints.NotNull;
+
+@Getter
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+public class PostRequestDto {
+
+    @NotNull
+    private String title;
+    @NotNull
+    private String content;
+    @NotNull
+    private Long created_userId;
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/request/UserRequestDto.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/request/UserRequestDto.java
new file mode 100644
index 0000000..75f5a8c
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/request/UserRequestDto.java
@@ -0,0 +1,30 @@
+package sopt.org.ThirdSeminar.controller.dto.request;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+import javax.validation.constraints.Email;
+import javax.validation.constraints.NotBlank;
+import javax.validation.constraints.NotNull;
+import javax.validation.constraints.Pattern;
+
+@Getter
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+public class UserRequestDto {
+    @Email(message = "이메일 형식이 맞지 않습니다.")
+    @NotNull
+    private String email;
+
+    @NotBlank
+    @Pattern(regexp = "^[가-힣a-zA-Z]{2,10}$", message = "닉네임 형식에 맞지 않습니다.")
+    private String nickname;
+
+    @NotBlank
+    @Pattern(regexp="(?=.*[0-9])(?=.*[a-zA-Z])(?=.*\\W)(?=\\S+$).{8,20}",
+            message = "비밀번호는 영문 대,소문자와 숫자, 특수기호가 적어도 1개 이상씩 포함된 8자 ~ 20자의 비밀번호여야 합니다."
+    )
+    private String password;
+
+
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/response/PostResponseDto.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/response/PostResponseDto.java
new file mode 100644
index 0000000..3bce587
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/response/PostResponseDto.java
@@ -0,0 +1,19 @@
+package sopt.org.ThirdSeminar.controller.dto.response;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+public class PostResponseDto {
+    private Long id;
+    private String title;
+    private String content;
+    private String created_user;
+
+    public static PostResponseDto of(Long id,String title,String content,String created_user){
+        return new PostResponseDto(id,title,content,created_user);
+    }
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/response/UserResponseDto.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/response/UserResponseDto.java
new file mode 100644
index 0000000..591b7d6
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/controller/dto/response/UserResponseDto.java
@@ -0,0 +1,17 @@
+package sopt.org.ThirdSeminar.controller.dto.response;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@Getter
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+public class UserResponseDto {
+
+    private Long userId;
+    private String nickname;
+
+    public static UserResponseDto of(Long userId, String nickname) {
+        return new UserResponseDto(userId, nickname);
+    }
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/domain/Post.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/domain/Post.java
new file mode 100644
index 0000000..c752f36
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/domain/Post.java
@@ -0,0 +1,32 @@
+package sopt.org.ThirdSeminar.domain;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import javax.persistence.*;
+
+@Entity
+@Getter
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class Post {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false)
+    private String title;
+    @Column(nullable = false)
+    private String content;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name="created_userId")
+    private User created_user;
+
+
+
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/domain/User.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/domain/User.java
new file mode 100644
index 0000000..36be36a
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/domain/User.java
@@ -0,0 +1,41 @@
+package sopt.org.ThirdSeminar.domain;
+
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import javax.persistence.*;
+import java.util.ArrayList;
+import java.util.List;
+
+@Entity
+@Getter
+@NoArgsConstructor
+public class User {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    public Long id;
+
+    @Column(nullable = false)
+    private String nickname;
+
+    @Column(nullable = false)
+    private String email;
+
+
+    @Column(nullable = false)
+    private String password;
+
+    @OneToMany(mappedBy = "created_user")
+    private List<Post> posts=new ArrayList<Post>();
+    @Builder
+    public User(String nickname,String email,String password){
+        this.nickname=nickname;
+        this.email=email;
+        this.password=password;
+        this.posts=new ArrayList<Post>();
+    }
+
+
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/exception/ErrorStatus.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/exception/ErrorStatus.java
new file mode 100644
index 0000000..0cdf79b
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/exception/ErrorStatus.java
@@ -0,0 +1,35 @@
+package sopt.org.ThirdSeminar.exception;
+
+import lombok.AccessLevel;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpStatus;
+
+@Getter
+@RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+public enum ErrorStatus {
+
+    /*
+BAD_REQUEST
+ */
+    VALIDATION_EXCEPTION(HttpStatus.BAD_REQUEST, "잘못된 요청입니다."),
+    VALIDATION_REQUEST_MISSING_EXCEPTION(HttpStatus.BAD_REQUEST, "요청값이 입력되지 않았습니다."),
+
+    NOT_FOUND_USER(HttpStatus.BAD_REQUEST, "검색 결과가 없습니다."),
+    /*
+    CONFLICT
+     */
+    CONFLICT_EMAIL_EXCEPTION(HttpStatus.CONFLICT, "이미 등록된 이메일입니다."),
+    CONFLICT_NICKNAME_EXCEPTION(HttpStatus.CONFLICT, "이미 등록된 닉네임입니다."),
+
+    /*
+    SERVER_ERROR
+     */
+    INTERNAL_SERVER_ERROR(HttpStatus.INTERNAL_SERVER_ERROR, "예상치 못한 서버 에러가 발생했습니다."),
+    BAD_GATEWAY_EXCEPTION(HttpStatus.BAD_GATEWAY, "일시적인 에러가 발생하였습니다.\n잠시 후 다시 시도해주세요!"),
+    SERVICE_UNAVAILABLE_EXCEPTION(HttpStatus.SERVICE_UNAVAILABLE, "현재 점검 중입니다.\n잠시 후 다시 시도해주세요!"),
+            ;
+
+    private final HttpStatus httpStatus;
+    private final String message;
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/exception/SuccessStatus.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/exception/SuccessStatus.java
new file mode 100644
index 0000000..73e02fd
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/exception/SuccessStatus.java
@@ -0,0 +1,19 @@
+package sopt.org.ThirdSeminar.exception;
+
+import lombok.AccessLevel;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpStatus;
+
+@Getter
+@RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+public enum SuccessStatus {
+
+
+    SIGNUP_SUCCESS(HttpStatus.CREATED,"회원가입이 완료되었습니다"),
+    SEARCH_SUCCESS(HttpStatus.OK,"유저 검색에 성공했습니다."),
+
+    CREATE_SUCCESS(HttpStatus.CREATED,"글 작성에 성공했습니다");
+    private final HttpStatus httpStatus;
+    private final String message;
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/infrastructure/PostRepository.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/infrastructure/PostRepository.java
new file mode 100644
index 0000000..57cad92
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/infrastructure/PostRepository.java
@@ -0,0 +1,17 @@
+package sopt.org.ThirdSeminar.infrastructure;
+
+
+import org.springframework.data.repository.Repository;
+import sopt.org.ThirdSeminar.domain.Post;
+
+import java.util.List;
+
+public interface PostRepository extends Repository<Post,Long> {
+
+    void save(Post post);
+
+    List<Post> findAllByTitle(String title);
+
+    Post getOne(Long id);
+
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/infrastructure/UserRepository.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/infrastructure/UserRepository.java
new file mode 100644
index 0000000..4e0f14e
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/infrastructure/UserRepository.java
@@ -0,0 +1,11 @@
+package sopt.org.ThirdSeminar.infrastructure;
+
+import org.springframework.data.repository.Repository;
+import sopt.org.ThirdSeminar.domain.User;
+
+public interface UserRepository extends Repository<User,Long> {
+    void save(User user) ;
+
+    User getOne(Long id);
+
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/service/PostService.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/service/PostService.java
new file mode 100644
index 0000000..0cbc885
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/service/PostService.java
@@ -0,0 +1,61 @@
+package sopt.org.ThirdSeminar.service;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import sopt.org.ThirdSeminar.controller.dto.request.PostRequestDto;
+import sopt.org.ThirdSeminar.controller.dto.response.PostResponseDto;
+import sopt.org.ThirdSeminar.domain.Post;
+import sopt.org.ThirdSeminar.domain.User;
+import sopt.org.ThirdSeminar.infrastructure.PostRepository;
+import sopt.org.ThirdSeminar.infrastructure.UserRepository;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class PostService {
+
+    private final PostRepository postRepository;
+    private final UserRepository userRepository;
+    @Transactional
+    public PostResponseDto create(PostRequestDto postRequestDto){
+
+        User user=userRepository.getOne(postRequestDto.getCreated_userId());
+        Post post= Post.builder()
+                .title(postRequestDto.getTitle())
+                .content(postRequestDto.getContent())
+                .created_user(user)
+                .build();
+        postRepository.save(post);
+        return PostResponseDto.of(post.getId(),post.getTitle(),post.getContent(),user.getNickname());
+    }
+
+    @Transactional
+    public PostResponseDto search(Long postId){
+
+        Post post= postRepository.getOne(postId);
+        User user=post.getCreated_user();
+        System.out.println(user);
+        PostResponseDto postResponseDto=PostResponseDto.of(post.getId(),post.getTitle(),post.getContent(),user.getNickname());
+
+        return postResponseDto;
+    }
+
+    @Transactional
+    public List<PostResponseDto> searchByTitle(String title){
+        List<Post> postList=postRepository.findAllByTitle(title);
+        
+        List<PostResponseDto> responseList=new ArrayList<PostResponseDto>();
+
+        for (Post post:postList
+             ) {
+            User user=post.getCreated_user();
+            responseList.add(PostResponseDto.of(post.getId(),post.getTitle(),post.getContent(),user.getNickname()));
+            
+        }
+
+        return responseList;
+    }
+}
diff --git a/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/service/UserService.java b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/service/UserService.java
new file mode 100644
index 0000000..74aa319
--- /dev/null
+++ b/ThirdSeminar/src/main/java/sopt/org/ThirdSeminar/service/UserService.java
@@ -0,0 +1,35 @@
+package sopt.org.ThirdSeminar.service;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import sopt.org.ThirdSeminar.controller.dto.request.UserRequestDto;
+import sopt.org.ThirdSeminar.controller.dto.response.UserResponseDto;
+import sopt.org.ThirdSeminar.domain.User;
+import sopt.org.ThirdSeminar.infrastructure.UserRepository;
+
+@Service
+@RequiredArgsConstructor
+public class UserService {
+
+    private final UserRepository userRepository;
+
+    @Transactional
+    public UserResponseDto create(UserRequestDto request){
+        User user= User.builder()
+                .email(request.getEmail())
+                .nickname(request.getNickname())
+                .password(request.getPassword())
+                .build();
+
+        userRepository.save(user);
+
+        return UserResponseDto.of(user.getId(), user.getNickname());
+    }
+
+    public UserResponseDto search(Long userId){
+        User user=userRepository.getOne(userId);
+
+        return UserResponseDto.of(user.getId(),user.getNickname());
+    }
+}
diff --git a/ThirdSeminar/src/main/resources/application.yaml b/ThirdSeminar/src/main/resources/application.yaml
new file mode 100644
index 0000000..c56a508
--- /dev/null
+++ b/ThirdSeminar/src/main/resources/application.yaml
@@ -0,0 +1,21 @@
+spring:
+  datasource:
+    driver-class-name: com.mysql.cj.jdbc.Driver
+    url: jdbc:mysql://localhost:3306/sopt_32?useSSL=true&useUnicode=true&serverTimezone=Asia/Seoul
+    username: sopt_server
+    password: 1124
+
+  jpa:
+    show-sql: true
+    hibernate:
+      ddl-auto: create
+    properties:
+      hibernate:
+        format_sql: true
+    logging:
+      level:
+        org:
+          hibernate:
+            type:
+              descriptor:
+                sql: trace
\ No newline at end of file
diff --git a/ThirdSeminar/src/test/java/sopt/org/ThirdSeminar/ThirdSeminarApplicationTests.java b/ThirdSeminar/src/test/java/sopt/org/ThirdSeminar/ThirdSeminarApplicationTests.java
new file mode 100644
index 0000000..c6d451e
--- /dev/null
+++ b/ThirdSeminar/src/test/java/sopt/org/ThirdSeminar/ThirdSeminarApplicationTests.java
@@ -0,0 +1,13 @@
+package sopt.org.ThirdSeminar;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class ThirdSeminarApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}