You can close the current drawing file without actually quitting AutoCAD by choosing Close > Current Drawing from the Application Menu or by entering CLOSE at the Command prompt. To close the current opened file or all opened files,
(i) Click on the Application button. Now Application menu appears.
(ii) Move the mouse to the Close button, then select either Current Drawing to dose the current file, or All Drawings to close all the opened files in single command.

To save your work and remain in AutoCAD:
1. Click the Save button in the Quick Access toolbar.
2. If the drawing has not yet been named, the Save Drawing As dialog box appears.
3. Name the drawing in the File name text box, and then choose Save.

Ribbon control panel are the Arc and Circle buttons found in ARC toul.

(i) Creating a rectangle using the LINE command, but doing so has some disadvantages.
(ii) For example, you would have to take the time to make sure that the comer angles are exactly 90°. Also, each line segment would be a separate object.
(iii) Therefore, AutoCAD 2016 provides the RECTANG command, which allows you to create a rectangle with perfect corners and as a single object.
(iv) Clicking anywhere on a rectangle created with the RECTANG command selects the entire rectangle.

(i) If the SNAP MODE button is chosen, the, snap mode will turn ON.
(ii) When snap is on, the cursor under mouse control can only be moved in jumps from one snap point to another.
(iii) The F9 key acts as a toggle key to turn the snap off or on.