7 segment display_PLEASE HELP.

I have connected four 7 segment displays (common anode) to mega 2560, they are all on by themselves as soon as I connect them, what's the reason they are on? How can I turn them off?

Thanks

What connections and what code?

If you intend to multiplex the displays, connect all the equivalent segment cathodes in parallel. The anodes you switch separately, probably each via a transistor.