Why do guys pinch my arms?

There's actually guys who do that, I know but why? i've experienced it twice now with two different guys.. they call my attention and pinch my arm. why do they do that? is it act of flirting? don't take me wrong i just dont know much about guys. :D
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+1 y
Guys, if you have time can I get a help from you for my other question? Thank you
www.girlsaskguys.com/.../q1655315-does-he-like-me-did-he-just-ask-me-out
Why do guys pinch my arms?
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