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Program control structures

Program control structures refer to how the flow of computer
instructions is managed. There are three types of program
control structures namely sequence, repetition and selection.
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Sequence structure in programming

In programming, a sequence structure follows the order of flow
of instructions or blocks from top to bottom. The first block is
executed before the next block. For example, in Figure 32,
blocks will be executed as follows.

1. The ‘when clicked’ block is executed first.

2. The ‘go to (random position)’ block is executed next.

3. The ‘turn (Q) 15 degrees’ block is then executed

4. Lastly, the ‘if on edge, bounce’ block is executed.

Figure 32: Sequence structure in programming

Thus, the flow becomes as follows: ‘When clicked → go to
(random position) → turn (15) degrees → if on edge, bounce’.

Repetition structure in programming

In computer programming, you might need some action to
repeat several times. For example, you might need movement

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