If I am buying a used iphone, do I juts put my sim card contained by?

I am buying a used 2g iphone, when I get it, do I just put my sim card contained by and start using it, or is something else required?

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You will need to put your sim card in and later plug the phone into your computer and activate it in itunes so you receive the data plan added to your account. Depends on if its unlocked or not. If it is after you would be able to, if not, after you would have to unlock it 1st.

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ITunes Won't Recognize my iPhone anymore?

Where do I check my notification on Facebook Mobile (for iPhone)?

I bought the unmarked 3g iphone and contained by usa and brought it hindmost to australia.?

I will be within London for 5 months and would approaching to find a UK phone number to use on my Iphone 3G from the US?

Using prepaid next to iPhone 3G.