Control Blocks

From the Scratch Wiki — made by Scratchers, for Scratchers.

Control blocks are one of the eight categories of Scratch blocks. They are color-coded yellow, and are used to control scripts.

There are currently four Hat blocks, six C blocks, four Stack blocks and two Cap blocks in this category.

Control blocks are essential for every project. Without Control blocks, a project would not be able to start or continue.

Blocks

Scratch 1.4 has the following four Control Hat blocks:

• When Green Flag Clicked
• When () Key Pressed
• When () Clicked
• When I Receive ()

Scratch 1.4 has the following six Control C blocks:

• Forever
• Repeat ()
• Forever if ()
• If ()
• If (), Else
• Repeat Until ()

Scratch 1.4 has the following four Control Stack blocks:

• Wait () Secs
• Broadcast ()
• Broadcast () and Wait
• Wait Until ()

Scratch 1.4 has the following two Control Cap blocks:

• Stop Script
• Stop All

Trigger Blocks

In the Experimental Viewer, Control blocks are separated into "Control" and "Triggers", in which Triggers are the hat blocks and the broadcast blocks, and Controls are the others. This is a hint that the Control blocks may be split into two separate groups in Scratch 2.0.

v • d • e Control Blocks
When Green Flag Clicked • When () Key Pressed • When () Clicked • Wait () Secs • Forever • Repeat () • Broadcast () • Broadcast () and Wait • When I Receive () • Forever if () • If () • If (), Else • Wait Until () • Repeat Until () • Stop Script                          • Stop AllMore blocks...

v • d • e Block Categories
Main Block Categories	Control Blocks • Motion Blocks • Looks Blocks • Sound Blocks • Pen Blocks • Sensing Blocks • Operators Blocks • Variables Blocks
Other Block Categories	Motor Blocks • List Blocks