Loops

Loops repeat a block of code — a fixed number of times (for) or while a condition holds (while).

Beginner

for — when you know how many times: iterate over a range or collection.
while — repeat while a condition stays true.
do-while (C, C++, Java) — runs at least once, then checks.

for i in range(5):        # 0, 1, 2, 3, 4
    print(i)

reading = read_sensor()
while reading < 100:
    reading = read_sensor()

break exits a loop early; continue skips to the next iteration.

In embedded code the main program is usually an intentional infinite loop (while (1) { ... } or Arduino's loop()), because the device should run forever.

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