What does -ar flag mean here:

cp -ar ../foo/bar/. qux/quux/ 

I'm quite new to command line languages and trying my best to learn it.

Not sure of the -ar flag only. -r is recursive right, then can you just add -a and it becomes -ar? is -a means all?

What does -ar flag mean here:

cp -ar ../foo/bar/. qux/quux/ 

I'm quite new to command line languages and trying my best to learn it.

Not sure of the -ar flag only. -r is recursive right, then can you just add -a and it becomes -ar? Does -a mean all?