diff --git a/README.md b/README.md
deleted file mode 100644
index d86263b..0000000
--- a/README.md
+++ /dev/null
@@ -1,2 +0,0 @@
-# todo
-레벨2
diff --git a/oop/errorMsg.js b/oop/errorMsg.js
new file mode 100644
index 0000000..782d421
--- /dev/null
+++ b/oop/errorMsg.js
@@ -0,0 +1,6 @@
+module.exports = {
+    'syntaxError' : "문법적으로 유효하지 않은 입력값입니다.",
+    'unknownIDError' : "ID 사용이 잘못되었습니다.",
+    'unknownID_duplicatedError' : "ID혹은 Status가 잘못되었습니다.",
+    'ELSE_ERROR' : "알 수 없는 오류가 발생했습니다." 
+}
\ No newline at end of file
diff --git a/oop/main.js b/oop/main.js
new file mode 100644
index 0000000..b14c491
--- /dev/null
+++ b/oop/main.js
@@ -0,0 +1,291 @@
+const readline = require('readline');
+const errorMsg = require('./errorMsg.js');
+const todoPrint = require('./todoPrint.js');
+
+
+const Print = new todoPrint.ShowPrint();
+
+
+let r = readline.createInterface({
+    input:process.stdin,
+    output:process.stdout
+});
+
+
+const showAllTimer = (input) => {
+    setTimeout(()=>{todoCommonMethod.todoCount()}, input);
+    setTimeout(()=>{r.prompt()} , input+1000) 
+}
+
+const ErrorCheck = class {
+    syntaxError(input) {
+        let firstWord = input.match(/\w+/); 
+        let seperator = input.match(/\$/g); 
+        let zeroSeperator = (firstWord[0] ==="undo" || firstWord[0] === "redo");
+        let oneSeperator = ((firstWord[0] === "delete" || firstWord[0] === "show") && (seperator.length===1));
+        let twoSeperator = ((firstWord[0] === "add" || firstWord[0] === "update") && (seperator.length===2));
+        if(zeroSeperator || oneSeperator || twoSeperator){
+            return true;
+        }else if (seperator === null){
+            return false;
+        }else {
+            return false;
+        }
+        
+    }
+    unknownIDError(ID) {
+        if(ID === NaN) {
+            return false;
+        } 
+        return !(todoModel.todoList.filter(v => v["id"] === ID).length === 0) ? true : false;
+    }
+    duplicatedStatusError(ID, status) {
+        return !(todoModel.todoList.filter(v => v["id"] === ID)[0]["status"] === status) ? true : false;
+    }
+}
+const Error = new ErrorCheck();
+
+const TodoCommonMethod = class {
+    todoCount() {
+        let todo = todoModel.todoList.filter(v => v.status === 'todo').length;
+        let doing = todoModel.todoList.filter(v => v.status === 'doing').length;
+        let done = todoModel.todoList.filter(v => v.status === 'done').length;
+    
+        Print.printShowAll(todo,doing,done);
+    }
+    
+    showElse(input) {
+        let temp = todoModel.todoList.filter(v => v.status === input).map((obj)=>{ return ` '${obj.name}, ${obj.id}번'`})
+        Print.printShowElse(temp.length, temp);
+    }
+    
+    makingID(){
+        return Math.floor(Math.random() * 10000);
+    }
+    
+    findDataIdObj(input){
+        let target = todoModel.todoList.filter(v => v["id"] === input);
+        let targetName = target[0].name;
+        let targetIdx = todoModel.todoList.indexOf(target[0]);    
+        return [targetIdx, targetName];
+    }
+}
+
+const todoCommonMethod = new TodoCommonMethod();
+
+
+const HistoryController = class {
+    constructor() {
+        this.undoHistory = [];
+        this.redoHistory = [];
+        this.HistoryForm = function (model, name, id, status, tag){
+            this.model = model;
+            this.name = name;
+            this.id = id;
+            this.status = status;
+            this.tag = tag;
+        }
+    }
+
+    historyLengthCheck(form){
+        if(this.undoHistory.length < 3) {
+            this.undoHistory.push(form);
+        } else {
+            this.undoHistory.shift();
+            this.undoHistory.push(form);
+        }
+    }
+
+    makeAddHistory(model, name, id, status, tag ){
+        let historyForm = new this.HistoryForm(model, name, id, status, tag);
+        this.historyLengthCheck(historyForm)
+    }
+
+    makeElseHistory(model, idx) {
+        let todoListData = todoModel.todoList[idx]
+        let [name, tag, status, id] = [todoListData['name'], todoListData['tag'], todoListData['status'], todoListData['id']];
+        let historyForm = new this.HistoryForm(model, name, id, status, tag );
+    
+        this.historyLengthCheck(historyForm)
+    }
+
+    undoModel(model) {
+        let target = this.undoHistory[this.undoHistory.length-1];
+        let [name, tag, status, id] = [target['name'], target['tag'], target['status'], target['id']];
+        
+        switch(model){
+        case 'add' :
+            this.undoAdd(id);
+            break;
+    
+        case 'update' :
+            this.undoUpdate(id, status);
+            break;
+    
+        case 'delete' :
+            this.undoDelete(id, name, tag, status)
+            break;
+        }
+    }   
+    
+    undoAdd(id) {
+        todoModel.delete(id)
+        this.undoHistory.pop();
+    }
+    undoUpdate(id, status) {
+        todoModel.update(id, status)
+        this.undoHistory.pop();
+    }
+    undoDelete(id, name, tag, status) {
+        let newTodoList = new todoModel.TodoForm(name, tag[0], status, id);
+        todoModel.todoList.push(newTodoList);
+        Print.printAdd(name,id);
+        showAllTimer(1000);
+    }  
+    
+    dataInput(input) {
+        this.redoHistory.push(input);
+    }
+    makeUpdateHistory(status) {
+        if(this.undoHistory[0] === undefined){
+            return;
+        }
+        this.undoHistory[this.undoHistory.length-1]['prev_status'] = status;
+    }
+    redoModel(model) {
+        let target = this.redoHistory[this.redoHistory.length-1];
+        let [name, tag, status, id, prev_status] = [target['name'], target['tag'], target['status'], target['id'], target['prev_status']];
+    
+        switch (model) {
+            case 'add' :
+                let newTodoList = new todoModel.TodoForm(name, tag[0], status, id);
+                todoModel.todoList.push(newTodoList);
+                Print.printAdd(name,id);
+                showAllTimer(1000);
+                this.undoHistory.pop();
+                break;
+            case 'update' :
+                todoModel.update(id, prev_status);
+                this.undoHistory.pop();
+                break;
+            case 'delete' :
+                todoModel.delete(id, name, tag, status);
+                this.undoHistory.pop();
+                break;
+        }
+    }      
+}
+const historyController = new HistoryController();
+
+
+const TodoModel = class{
+
+    constructor() {
+        this.todoList = [{ name: 'sfd', tag: [ 'sdf' ], status: 'todo', id: 2614 } ];
+        this.TodoForm = function (name, tag, status, id) {
+            this.name = name;
+            this.tag = [tag];
+            this.status = status;
+            this.id = id;
+        }
+    }    
+    show(input) {
+        let status = input[0];
+        status === 'all' ? todoCommonMethod.todoCount() : todoCommonMethod.showElse(status);
+    }
+    add(input) {
+        let [name, tag] = input;
+        let id = todoCommonMethod.makingID();
+        let newTodoList = new this.TodoForm(name, tag, 'todo', id);
+        historyController.makeAddHistory("add", name, id, 'todo', tag );
+
+        this.todoList.push(newTodoList);
+        
+        Print.printAdd(name,id);
+        showAllTimer(1000);
+    }
+    delete(id) {
+        let [targetIdx, targetName] = todoCommonMethod.findDataIdObj(id)
+        historyController.makeElseHistory('delete', targetIdx);
+        this.todoList.splice(targetIdx,1);
+    
+        Print.printDelete(targetName);
+        showAllTimer(1000);
+    }
+    update(id, status) {
+        let [targetIdx, targetName] = todoCommonMethod.findDataIdObj(id)
+        historyController.makeElseHistory('update', targetIdx);
+        this.todoList[targetIdx].status = status;
+        historyController.makeUpdateHistory(status);
+
+        setTimeout(()=>{Print.printUpdate(targetName, status)}, 1000);
+        showAllTimer(4000);
+    } 
+    
+}
+
+
+const todoModel = new TodoModel();
+
+const arr = "update$2614$doing"
+
+const todoMain = (answer) => {
+    if(!Error.syntaxError(answer)) {
+        Print.printError(errorMsg.syntaxError);
+        return true;
+    }
+    
+    let tempArr = answer.match(/\w+/g);
+    let action = tempArr.shift(0);   
+
+    if(action === "add") {
+        todoModel.add(tempArr);
+
+    } else if(action === "delete") { 
+        tempArr[0] = Number(tempArr[0])
+        let ID = tempArr[0]
+        !Error.unknownIDError(ID) ? Print.printError(errorMsg.unknownIDError) : todoModel.delete(ID);
+        
+    } else if(action === "update") { 
+        tempArr[0] = Number(tempArr[0])
+        let ID = tempArr[0]
+        let status = tempArr[1]
+        !Error.unknownIDError(ID) || !Error.duplicatedStatusError(ID,status) ? Print.printError(errorMsg.unknownID_duplicatedError) : todoModel.update(ID, status)
+
+    } else if(action === "show") {
+        todoModel.show(tempArr);
+
+    } else if(action === 'undo') {
+        let data = historyController.undoHistory;
+        let dataLength = data.length-1;
+        historyController.undoModel(data[dataLength]['model']);
+        historyController.redoHistory.push(data[dataLength]);
+        data.pop();
+        
+    } else if(action === 'redo') {
+        let data = historyController.redoHistory;
+        let dataLength = data.length-1;
+        historyController.redoModel(data[dataLength]['model']);
+        data.pop();
+
+    } else {
+        Print.printError(errorMsg.ELSE_ERROR);
+    }
+
+    
+    console.log(todoModel.todoList);
+    console.log(historyController.undoHistory);
+    console.log(historyController.redoHistory);
+
+}
+
+
+
+ r.setPrompt('명령하세요 : ');
+ r.prompt();
+ r.on('line', (answer) => {
+    
+    todoMain(answer);
+
+ })
+
diff --git a/oop/todoPrint.js b/oop/todoPrint.js
new file mode 100644
index 0000000..6011c0b
--- /dev/null
+++ b/oop/todoPrint.js
@@ -0,0 +1,26 @@
+const ShowPrint = class {
+    printShowAll(todo, doing, done){
+        console.log(`현재 상태 : todo: ${todo}개, doing: ${doing}개, done: ${done}개`)
+    }
+    printShowElse(temp_length, temp){
+        console.log(`${this.value1}리스트 : 총 ${temp_length}건 : ${temp}`);
+    }
+    printAdd(name,id){
+        console.log(`${name} 1개가 추가됐습니다. (id : ${id})`);
+    }
+    printUpdate(targetName, status){
+        console.log(`${targetName} 가 ${status}상태로 변경되었습니다.`);
+    }
+    printDelete(targetName){
+        console.log(`${targetName} 가 todo에서 삭제되었습니다.`)
+    }
+    printError(errorKey){
+        console.log(errorKey)
+    }
+}
+
+
+
+module.exports = {
+    ShowPrint
+}