What do AF-A, AF-C, and AF-S mean?

Question

My camera has these settings for autofocus, and I don't know what they mean. I suspect "A" is "Auto", and "C" is "continuous", but I have no idea what "S" is.

Answer

This link explains it well. Paraphrasing the article:

• AF-C (AF-continuous or servo mode) is used for photographing moving subjects.
• AF-S means single shot and is used for subject that is stationary.
• AF-A is where the camera decides whether the subject is moving or not and tries to alternate between the servo and single shot mode accordingly.

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