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Some of the common categories of blocks are Motion, Looks, Sound, Events, Control, Sensing,
                  Operators, and Pen.


                   Block category                                           Use

                                      These blocks are used to control the movements of your Sprites.
                         Motion

                                      These blocks control what your Sprites and backdrop look like.
                         Looks


                                      These blocks are used to play or stop sounds.
                         Sound
                                      These blocks are fundamental blocks. Each script has an event at its start
                         Events       which tells the script to run.

                                      These blocks control the blocks within your scripts, inserting conditional
                         Control      statements, loops, repeats and pauses.

                                      These blocks identify  what’s  happening  at  a  given  point  and  make your
                         Sensing      Sprites or background respond to user actions.

                                      These blocks let you make comparisons or perform arithmetic functions on
                        Operators     different values.

                                      These blocks are used to draw shapes and patterns on the stage, change the
                                      pen color and size.
                          Pen


                   i +  USE OF FOREVER AND FOREVER-IF BLOCKS
                  All the programs or projects developed till now run only once. If you want to run a set of statements
                  more than once, you will either run the code again or write the script again. In Scratch, we can
                  save our time and effort by repeating the code without writing the program again or writing the
                  script again. The automatic running of a set of instructions more than once is called looping. The
                  blocks for looping are given in Control category.

                  The Repeat block is used to run a set of instructions for a specified number
                  of times.

                                      The Repeat Until block is used to run a set of instructions till a condition is
                                      satisfied.


                  The  Forever block is  used to run a set of instructions continuously until
                  stopped. The instructions inside this block will be executed in a loop until the
                  Stop button       is clicked by the user.

                  The Repeat and Repeat Until blocks can be used to display the table of a number input by the
                  user. The script for the sprite can be like this (using Repeat Until block).





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