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VARIABLES
A program is a set of 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.
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 changes. You can modify this value of a variable according to your script.
Types of Variables
There are two types of variables. They are as follows:
Global Variables
If a variable is created to be used and modified by all the Sprites, then it is known
as a global variable. A Global variable can be created on any Sprite but its value
can be accessed or modified by other Sprites used in the project.
Local Variables
If a variable is created to be used and modified by a single Sprite only, then it is
known as a local variable. Local variables can only be accessed or modified from
the Sprite where it was created.
Creating Variables in Scratch
To create variables in Scratch, follow the given steps:
Step 1: Click on Variables block category. A set
of blocks appears in the block palette. 2
Step 2: Click on Make a Variable block. A New
Variable dialog box appears. Type a
variable name in the New variable
name box.
Step 3: Click on the radio button of either of
the options. Click on For all sprites if
you want this variable to appear for all
the sprites. 1
Or
Click on For this sprite only if you want
this variable to appear for this sprite only. Here we have added the variable
fruit. It will be available for all the sprites.
90 Play (Ver. 2.1)-V

