BLOCK:
1. WRITE BLOCK W ENTER
2. MAKE BLOCK B ENTER
WRITE BLOCK; WE CAN SAVE THIS BLOCK IN COMPUTER AND CALL THIS FOR OTHER PROJECT
MAKE BLOCK: WE CAN CALL THIS BLOCK ONLY WITHIN THE SAME PROJECT
APPLICATIONS:
1. TO MAKE ENTITIES SINGLE.
2. WE CAN USE THE BLOCK FOR CREATING DRAWING SYMBOLS
3. TO CREATE TEMPLATES
4. TO STANDARDISE THE DRAWING SO THAT WE CAN CALL IT FOR OTHER DRAWINGS