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CONDITIONS

There are situations in life when we need to decide based on a situation. For example, if it rains, we will stay
at home, or else we will visit the market. Similar situations arise in programming as well, where we need to
make some decisions and based on these decisions, execute a set of commands. We need to determine
which action is to be taken and which statement is to be executed, if the outcome is true or false.

Conditions in Programming

Conditions are like questions that a computer asks to make a decision. They check if something is true
or false. If the answer is true, the computer does one thing. If it is false, it can do something else or
nothing at all. For example, if it is raining, you take an umbrella. If it is not raining, you don’t take one.
In programming, conditions help the computer decide what to do next.

Conditional statements, also known as decision-making, are used in programming to execute different
blocks of code based on certain conditions. The following conditional blocks are available in Scratch:

If-then block

If-then-else block

If-then block

The If-then block in Scratch checks a condition. If the condition is true, it runs the blocks inside it. If the
condition is false, it skips the blocks and does nothing.
For example, to say 'Hello!' if spacebar key pressed while touching pointer, use the following script:

The above script shows how an if-then block creates conditional behaviour in Scratch. When the
spacebar key is pressed, the script starts running and checks if the mouse pointer is touching the
sprite. Only when both conditions are true will the sprite say "Hello!" for two seconds. The if-then block
is a conditional statement that ensures the greeting happens only when the user presses spacebar key
while pointing at the sprite.

The block is an event block. Scripts placed underneath this block will activate when

the specified key is pressed.

If-then-else block

The If-then-else block in Scratch checks a condition. If the condition is true, it runs the blocks inside the if
part. If the condition is false, it runs the blocks inside the else part.

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