String cheese is distinctly American so I'm not surprised some people have never seen it.
Basically it's just mozzarella cheese (you guys know what that is, right?) that is shaped like a tube in a way that you can peel it length-wise. The proper way to eat it is to peel off "strings" and eat the individual strings, which makes the relatively small piece of cheese take a pretty long time to eat, but it makes it a lot more delicious.
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_foolmo_
'Oh please, if foolmo made that analogy you'd think it was picture perfect' - Biolizard28