Some technical problems running my code through Chrome

    // Problem: User Interaction doesn't provide desired results
    // Solution: Add interactivety so the user can manage daily tasks

    var taskInput = document.getElementById("new-task"); // new-task
    var addButton = document.getElementsByTagName("button")[0]; // first button
    var incompleteTasksHolder = document.getElementById("incomplete-tasks"); // incomplete-tasks
    var completedTasksHolder = document.getElementById("completed-tasks"); // completed-tasks

    // New task List Item
    var createNewTaskElement = function ( taskString ){
        // Create List Item
        var listItem = document.createElement("li");

            // input (checkbox)
            var checkBox = document.createElement("input");
            // label
            var label = document.createElement("label");
            // input (text)
            var editInput = document.createElement("input");
            // button, edit
            var editButton = document.createElement("button");
            // button, delete
            var deleteButton = document.createElement("button");

            // Each element needs to be modified 
            checkBox.type = "checkbox";
            editInput.type = "text";

            editButton.innerText = "Edit";
            editButton.className = "edit";
            deleteButton.innerText = "Delete";
            deleteButton.className = "delete";

            label.innerText = taskString;
            // And appended
            listItem.appendChild(checkBox);
            listItem.appendChild(label);
            listItem.appendChild(editInput);
            listItem.appendChild(editButton);
            listItem.appendChild(deleteButton);

        return listItem;
    }

    // Add a new task
    var addTask = function () {
        console.log("Add task...");
        // Create a new list item with the text from #new-task:
        var listItem = createNewTaskElement(taskInput.value);

        // Append listItem to incompleteTasksHolder
        incompleteTasksHolder.appendChild(listItem);
        bindTaskEvents( listItem, taskCompleted );
    }

    // Edit an existing task
    var editTask = function () {
        console.log("Edit task...");

        var listItem = this.parentNode;

        var editInput = listItem.querySelector("input[type=text]");
        var label = listItem.querySelector("label");

        var containsClass = listItem.classList.contains("editMode");

        // If the class of the parent is .editMode
        if ( containsClass ) {
            // Switch from .editMode
            // Label text to become the input's value
            label.innerText = editInput.value;
        } else {
            // Switch to .editMode
            // input value becomes the label's text
            editInput.value = label.innerText;
        }

        // Toggle .editMode on the parent (list item)
        listItem.classList.toggle("editMode");
    }


    // Mark a task as complete
    var taskCompleted = function () {
        console.log("Completed task...");
        // Append the task list item to the #completed-tasks
        var listItem = this.parentNode;
        completedTasksHolder.appendChild(listItem);
        bindTaskEvents ( listItem, taskIncomplete );
    }


    // Mark a task as incomplete
    var taskIncomplete = function () {
        console.log("Incompleted task...");
        // Append the task list item to the #incomplete-tasks
        var listItem = this.parentNode;
        incompleteTasksHolder.appendChild(listItem);
        bindTaskEvents( listItem, taskCompleted );
    }


    // Delete an existing task
    var deleteTask = function () {
        console.log("Delete task...");

        var listItem = this.parentNode;
        var ul = listItem.parentNode;

        // Remove the parent list item from the ul
        ul.removeChild(listItem);
    }

    var bindTaskEvents = function ( taskListItem, checkBoxEventHandler ) {
        console.log("Bind list item events");
        // Select taskListItem's children
        var checkBox = taskListItem.querySelector("input[type=checkbox]");
        var editButton = taskListItem.querySelector("button.edit");
        var deleteButton = taskListItem.querySelector("button.delete");

        // Bind editTask to edit button
        editButton.onclick = editTask;

        // Bind deleteTask to delete button
        deleteButton.onclick = deleteTask;

        // Bind checkBoxEventHandler to checkbox
        checkBox.onchange = checkBoxEventHandler;
    }


    // Set the click handler to the addTask function
    addButton.onclick = addTask;


    // Cycle over incompleteTasksHolder ul list items
    for(var i = 0; i < incompleteTasksHolder.children.length; i++) {
        // Bind events to list item's children (taskCompleted)
        bindTaskEvents(incompleteTasksHolder.children[i], taskCompleted);
    }

    // Cycle over completedTasksHolder ul list items
    for(var i = 0; i < completedTasksHolder.children.length; i++) {
        // Bind events to list item's children (taskIncomplete)
        bindTaskEvents(completedTasksHolder.children[i], taskIncomplete);
    }