diff --git a/dist/app.js b/dist/app.js
new file mode 100644
index 0000000..2d982eb
--- /dev/null
+++ b/dist/app.js
@@ -0,0 +1,26 @@
+"use strict";
+// const ADMIN = 0;
+// const READ_ONLY = 1;
+// const AUTHOR = 2;
+var Role;
+(function (Role) {
+    Role[Role["ADMIN"] = 0] = "ADMIN";
+    Role[Role["READ_ONLY"] = 1] = "READ_ONLY";
+    Role[Role["AUTHOR"] = 2] = "AUTHOR";
+})(Role || (Role = {}));
+var person = {
+    name: 'Maximilian',
+    age: 30,
+    hobbies: ['Sports', 'Cooking'],
+    role: Role.ADMIN, //0
+};
+person.role = Role.READ_ONLY;
+if (person.role === Role.ADMIN) {
+    console.log(person.role);
+}
+else if (person.role === Role.READ_ONLY) {
+    console.log(person.role);
+}
+else if (person.role === Role.AUTHOR) {
+    console.log(person.role);
+}
diff --git a/dist/basics.js b/dist/basics.js
new file mode 100644
index 0000000..badc6c2
--- /dev/null
+++ b/dist/basics.js
@@ -0,0 +1,16 @@
+"use strict";
+function add(n1, n2, showResult, phrase) {
+    var result = n1 + n2; //result는 number라고 추론을 한다.
+    if (showResult) {
+        console.log(result + phrase);
+    }
+    else {
+        return n1 + n2;
+    }
+}
+var number1 = 5;
+var number2 = 2.8;
+var printResult = true;
+var resultPhrase = 'Result is: ';
+// resultPhrase = 0;  //error -> 타입 추론으로 resultPhrase는 string이다. 따라 0이라는 number타입을 할당할 수 없다.
+add(number1, number2, printResult, resultPhrase);
diff --git a/package-lock.json b/package-lock.json
index 8c52b80..1ff00b0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,218 +1,217 @@
-{
-  "name": "typescript-lecture",
-  "version": "0.0.0",
-  "lockfileVersion": 3,
-  "requires": true,
-  "packages": {
-    "": {
-      "name": "typescript-lecture",
-      "version": "0.0.0",
-      "license": "ISC",
-      "dependencies": {
-        "typescript": "^5.5.4"
-      },
-      "devDependencies": {
-        "ts-node": "^10.9.2"
-      }
-    },
-    "node_modules/@cspotcode/source-map-support": {
-      "version": "0.8.1",
-      "resolved": "https://registry.npmjs.org/@cspotcode/source-map-support/-/source-map-support-0.8.1.tgz",
-      "integrity": "sha512-IchNf6dN4tHoMFIn/7OE8LWZ19Y6q/67Bmf6vnGREv8RSbBVb9LPJxEcnwrcwX6ixSvaiGoomAUvu4YSxXrVgw==",
-      "dev": true,
-      "dependencies": {
-        "@jridgewell/trace-mapping": "0.3.9"
-      },
-      "engines": {
-        "node": ">=12"
-      }
-    },
-    "node_modules/@jridgewell/resolve-uri": {
-      "version": "3.1.2",
-      "resolved": "https://registry.npmjs.org/@jridgewell/resolve-uri/-/resolve-uri-3.1.2.tgz",
-      "integrity": "sha512-bRISgCIjP20/tbWSPWMEi54QVPRZExkuD9lJL+UIxUKtwVJA8wW1Trb1jMs1RFXo1CBTNZ/5hpC9QvmKWdopKw==",
-      "dev": true,
-      "engines": {
-        "node": ">=6.0.0"
-      }
-    },
-    "node_modules/@jridgewell/sourcemap-codec": {
-      "version": "1.5.0",
-      "resolved": "https://registry.npmjs.org/@jridgewell/sourcemap-codec/-/sourcemap-codec-1.5.0.tgz",
-      "integrity": "sha512-gv3ZRaISU3fjPAgNsriBRqGWQL6quFx04YMPW/zD8XMLsU32mhCCbfbO6KZFLjvYpCZ8zyDEgqsgf+PwPaM7GQ==",
-      "dev": true
-    },
-    "node_modules/@jridgewell/trace-mapping": {
-      "version": "0.3.9",
-      "resolved": "https://registry.npmjs.org/@jridgewell/trace-mapping/-/trace-mapping-0.3.9.tgz",
-      "integrity": "sha512-3Belt6tdc8bPgAtbcmdtNJlirVoTmEb5e2gC94PnkwEW9jI6CAHUeoG85tjWP5WquqfavoMtMwiG4P926ZKKuQ==",
-      "dev": true,
-      "dependencies": {
-        "@jridgewell/resolve-uri": "^3.0.3",
-        "@jridgewell/sourcemap-codec": "^1.4.10"
-      }
-    },
-    "node_modules/@tsconfig/node10": {
-      "version": "1.0.11",
-      "resolved": "https://registry.npmjs.org/@tsconfig/node10/-/node10-1.0.11.tgz",
-      "integrity": "sha512-DcRjDCujK/kCk/cUe8Xz8ZSpm8mS3mNNpta+jGCA6USEDfktlNvm1+IuZ9eTcDbNk41BHwpHHeW+N1lKCz4zOw==",
-      "dev": true
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-    "node_modules/@tsconfig/node12": {
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-      "resolved": "https://registry.npmjs.org/@tsconfig/node12/-/node12-1.0.11.tgz",
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-      "dev": true
-    },
-    "node_modules/@tsconfig/node14": {
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-      "resolved": "https://registry.npmjs.org/@tsconfig/node14/-/node14-1.0.3.tgz",
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-      "dev": true
-    },
-    "node_modules/@tsconfig/node16": {
-      "version": "1.0.4",
-      "resolved": "https://registry.npmjs.org/@tsconfig/node16/-/node16-1.0.4.tgz",
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-      "dev": true,
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-      "dependencies": {
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-      "dev": true,
-      "bin": {
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-      },
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-      "dev": true,
-      "engines": {
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-    },
-    "node_modules/make-error": {
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-      "dev": true
-    },
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-      "resolved": "https://registry.npmjs.org/ts-node/-/ts-node-10.9.2.tgz",
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-        "@tsconfig/node10": "^1.0.7",
-        "@tsconfig/node12": "^1.0.7",
-        "@tsconfig/node14": "^1.0.0",
-        "@tsconfig/node16": "^1.0.2",
-        "acorn": "^8.4.1",
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-        "ts-node-script": "dist/bin-script.js",
-        "ts-node-transpile-only": "dist/bin-transpile.js",
-        "ts-script": "dist/bin-script-deprecated.js"
-      },
-      "peerDependencies": {
-        "@swc/core": ">=1.2.50",
-        "@swc/wasm": ">=1.2.50",
-        "@types/node": "*",
-        "typescript": ">=2.7"
-      },
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-        "@swc/core": {
-          "optional": true
-        },
-        "@swc/wasm": {
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-        }
-      }
-    },
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-        "tsserver": "bin/tsserver"
-      },
-      "engines": {
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-      }
-    },
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-      "dev": true,
-      "engines": {
-        "node": ">=6"
-      }
-    }
-  }
-}
+{
+  "name": "typescript-lecture",
+  "version": "0.0.0",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "typescript-lecture",
+      "version": "0.0.0",
+      "license": "ISC",
+      "devDependencies": {
+        "ts-node": "^10.9.2",
+        "typescript": "^5.5.4"
+      }
+    },
+    "node_modules/@cspotcode/source-map-support": {
+      "version": "0.8.1",
+      "resolved": "https://registry.npmjs.org/@cspotcode/source-map-support/-/source-map-support-0.8.1.tgz",
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+      "dev": true,
+      "dependencies": {
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+      },
+      "engines": {
+        "node": ">=12"
+      }
+    },
+    "node_modules/@jridgewell/resolve-uri": {
+      "version": "3.1.2",
+      "resolved": "https://registry.npmjs.org/@jridgewell/resolve-uri/-/resolve-uri-3.1.2.tgz",
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+      "dev": true,
+      "engines": {
+        "node": ">=6.0.0"
+      }
+    },
+    "node_modules/@jridgewell/sourcemap-codec": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/@jridgewell/sourcemap-codec/-/sourcemap-codec-1.5.0.tgz",
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+    },
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+        "@jridgewell/sourcemap-codec": "^1.4.10"
+      }
+    },
+    "node_modules/@tsconfig/node10": {
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+    },
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+    },
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+      "peer": true,
+      "dependencies": {
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+      }
+    },
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+      "dev": true,
+      "bin": {
+        "acorn": "bin/acorn"
+      },
+      "engines": {
+        "node": ">=0.4.0"
+      }
+    },
+    "node_modules/acorn-walk": {
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+      "dev": true,
+      "dependencies": {
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+      },
+      "engines": {
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+      }
+    },
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+      "dev": true,
+      "engines": {
+        "node": ">=0.3.1"
+      }
+    },
+    "node_modules/make-error": {
+      "version": "1.3.6",
+      "resolved": "https://registry.npmjs.org/make-error/-/make-error-1.3.6.tgz",
+      "integrity": "sha512-s8UhlNe7vPKomQhC1qFelMokr/Sc3AgNbso3n74mVPA5LTZwkB9NlXf4XPamLxJE8h0gh73rM94xvwRT2CVInw==",
+      "dev": true
+    },
+    "node_modules/ts-node": {
+      "version": "10.9.2",
+      "resolved": "https://registry.npmjs.org/ts-node/-/ts-node-10.9.2.tgz",
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+      "dev": true,
+      "dependencies": {
+        "@cspotcode/source-map-support": "^0.8.0",
+        "@tsconfig/node10": "^1.0.7",
+        "@tsconfig/node12": "^1.0.7",
+        "@tsconfig/node14": "^1.0.0",
+        "@tsconfig/node16": "^1.0.2",
+        "acorn": "^8.4.1",
+        "acorn-walk": "^8.1.1",
+        "arg": "^4.1.0",
+        "create-require": "^1.1.0",
+        "diff": "^4.0.1",
+        "make-error": "^1.1.1",
+        "v8-compile-cache-lib": "^3.0.1",
+        "yn": "3.1.1"
+      },
+      "bin": {
+        "ts-node": "dist/bin.js",
+        "ts-node-cwd": "dist/bin-cwd.js",
+        "ts-node-esm": "dist/bin-esm.js",
+        "ts-node-script": "dist/bin-script.js",
+        "ts-node-transpile-only": "dist/bin-transpile.js",
+        "ts-script": "dist/bin-script-deprecated.js"
+      },
+      "peerDependencies": {
+        "@swc/core": ">=1.2.50",
+        "@swc/wasm": ">=1.2.50",
+        "@types/node": "*",
+        "typescript": ">=2.7"
+      },
+      "peerDependenciesMeta": {
+        "@swc/core": {
+          "optional": true
+        },
+        "@swc/wasm": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/typescript": {
+      "version": "5.5.4",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.5.4.tgz",
+      "integrity": "sha512-Mtq29sKDAEYP7aljRgtPOpTvOfbwRWlS6dPRzwjdE+C0R4brX/GUyhHSecbHMFLNBLcJIPt9nl9yG5TZ1weH+Q==",
+      "dev": true,
+      "bin": {
+        "tsc": "bin/tsc",
+        "tsserver": "bin/tsserver"
+      },
+      "engines": {
+        "node": ">=14.17"
+      }
+    },
+    "node_modules/undici-types": {
+      "version": "6.19.8",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.19.8.tgz",
+      "integrity": "sha512-ve2KP6f/JnbPBFyobGHuerC9g1FYGn/F8n1LWTwNxCEzd6IfqTwUQcNXgEtmmQ6DlRrC1hrSrBnCZPokRrDHjw==",
+      "dev": true,
+      "peer": true
+    },
+    "node_modules/v8-compile-cache-lib": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/v8-compile-cache-lib/-/v8-compile-cache-lib-3.0.1.tgz",
+      "integrity": "sha512-wa7YjyUGfNZngI/vtK0UHAN+lgDCxBPCylVXGp0zu59Fz5aiGtNXaq3DhIov063MorB+VfufLh3JlF2KdTK3xg==",
+      "dev": true
+    },
+    "node_modules/yn": {
+      "version": "3.1.1",
+      "resolved": "https://registry.npmjs.org/yn/-/yn-3.1.1.tgz",
+      "integrity": "sha512-Ux4ygGWsu2c7isFWe8Yu1YluJmqVhxqK2cLXNQA5AcC3QfbGNpM7fu0Y8b/z16pXLnFxZYvWhd3fhBY9DLmC6Q==",
+      "dev": true,
+      "engines": {
+        "node": ">=6"
+      }
+    }
+  }
+}
diff --git a/package.json b/package.json
index 1148aaa..d8e39e3 100644
--- a/package.json
+++ b/package.json
@@ -11,10 +11,8 @@
   },
   "author": "",
   "license": "ISC",
-  "dependencies": {
-    "typescript": "^5.5.4"
-  },
   "devDependencies": {
-    "ts-node": "^10.9.2"
+    "ts-node": "^10.9.2",
+    "typescript": "^5.5.4"
   }
-}
\ No newline at end of file
+}
diff --git a/src/app.ts b/src/app.ts
index 16e7654..370c7a3 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -1,26 +1,26 @@
-const person: {
-  name: string,
-  age: number,
-  hobbies: string[];
-  role: (number | string)[];
-} = {
+// const ADMIN = 0;
+// const READ_ONLY = 1;
+// const AUTHOR = 2;
+
+enum Role {
+  ADMIN = 5, READ_ONLY = 'READ_ONLY', AUTHOR = 100  //이후로는 +1씩 증가를 한다.
+};
+
+const person = {
   name: 'Maximilian',
   age: 30,
   hobbies: ['Sports', 'Cooking'],
-  //tuple 튜플은 유니온 타입으로 구성되어 있다.
-  role: [2, 'author']
+  role: Role.ADMIN,  //0
 };
 
-//유니온으로 구성되어 있기 떄문에 number와 string으로 값을 재할당할 수 있다.
-person.role.push('admin');  //push는 튜플에서 허용되는 예외이다. 오류를 잡지 못한다.
-person.role[1] = 10;  //error -> string을 할당할 수 없다.
-person.role = [0, 'admin', 'user']; //이러한 추가 방식도 에러가 발생한다.
-
-let favoriteActivities: string[];
-favoriteActivities = ['Sports'];
-
-console.log(person.name);
+// person.role = Role.READ_ONLY;
+// error -> error TS2367: This comparison appears to be unintentional because the types 'Role.READ_ONLY' and 'Role.ADMIN' have no overlap.
+// 원인 : person.role이 Role.READ_ONLY로 설정된 후, TypeScript는 person.role이 더 이상 Role.ADMIN과 같은 값이 될 수 없다고 판단하는 것
 
-for (const hobby of person.hobbies) {
-  console.log(hobby);
-}
\ No newline at end of file
+if (person.role === Role.ADMIN) {
+  console.log(person.role);
+} else if (person.role === Role.READ_ONLY) {
+  console.log(person.role);
+} else if (person.role === Role.AUTHOR) {
+  console.log(person.role);
+}
diff --git a/tsconfig.json b/tsconfig.json
index 0464f8b..9ff2721 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -14,7 +14,7 @@
    "noFallthroughCasesInSwitch": true,
    "module": "commonjs",
    "outDir": "dist",
-   "rootDir": "src",
+   "rootDir": "src"
  },
  "include": [
    "src/**/*"