Page 110 - TP_Plus_v4_Class4
P. 110

VARIABLES


              A program is a group of commands and instructions that tell the computer to carry out a
              task. In scratch, a program is called a script. A script is made up of a number of blocks. So, the
              blocks are the commands or instructions that we give to the sprite to perform a task. In Scratch
              you can make programs to create games, stories and animations.

              All the numbers, text, date or pictures that we use in a program are called data. We store
              this data in the computer memory so that we can get information from it later. This data is
              stored in variables. It is called variable because it does not have a fixed value, its value varies
              or changes. For example, in the move block, the variable has a value 10 by default. You can

              modify this value according to your script. Variables can store numbers as well as letters.

              Creating Variables in Scratch

              To create variables in Scratch, follow the given steps:


                 2   Click on Make a                                    Type a variable name
                     Variable block.                                    in the New variable
                                                                    3
                                                                        name box.




                                                                                                    Click  on  the
                                                                                                    radio button
                                                                                                    of  either  of   4
                                                                                                    the options.


                1   Click on Variables
                    block category.


                                                                      5
                                                                          Click on Ok button.


              Click on For this sprite only if you want this variable to appear for the selected sprite only.
              Here, we have added the variable fruit. It will be available for all the sprites.

              The variable appears in the
              list of  Variables blocks.                                            ask Which is your favourite fruit?  and wait

              Observe that the variable                                             set  fruit   to answer
              name fruit appears in all the                                         say  answer  for 4  seconds
              blocks.

                Now  create  the  following                                         Factbot
              script:
                                                                             Every time you type a name or number,
                                                                             the previous value in the variable gets
                                                                             deleted and the new value is stored.



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