When I read some events map, I found loops used wildly. But some equipment watches like Timex used laps. What's the difference, how can I use them correctly? Please also give some sample if possible.
It appears to be the case that a loop is the word you would use to describe all or a section of a course or track which repeats upon itself (i.e. in a loop). In contrast, a lap is the description of physically running around that loop more than once.
From the online Cambridge dictionary for lap:
a complete journey around a race track that is repeated several times during a competition
The definition of loop has no reference to "looping" around a race track, but it does state, as an example:
Turn left where the road loops round the farm buildings.
This implies that loop could be used to describe the curved path something takes, which at a stretch suggests it could be used in place of lap, but it certainly doesn't seem like intended usage.
Here in the UK, Laps is the recognised term; I've only ever heard Loops used by Americans.
As for correct, I'd argue that either is correct, While one or the other might be more commonly used in different cultures, the meaning is clear from both.
Laps is used for any very well-defined "course" like a track or in a swimming pool, but loop is used for something that is a bit more ambiguous or out of immediate sight, like a cross country or driving course.