AR-15's, AK-47's, etc. use magazines.
M-1 Garand, Carcano, etc. use clips
Mausers, Enfields, etc. use strippers (aka chargers).
The difference between a "clip" and a "charger" is that the clip stays in the weapon till the last round is fired, while the charger is only used to insert the rounds into the magazine and is then removed. I know, it is kind of nitpicky, but technically there is a difference. In the end, it doesn't matter if you know what it's called, only that you know how to use them effectively.
"You can tell who knows what they are doing by looking in those ammo cans.The wooden crates, spam cans and paper boxes are long gone. In place of the crate, two cans are left with inspected and clipped ammo at ready. They have purchased all of the system components and have them properly prepared in advance. They store their gear this way from day one." -Brew
The truly prepared not only have the rounds in clips, magazines, or strippers, but also have these stored in bandoliers. Just reach in the can, grab a couple, and go.