yes 7 people can play at the same time on certain games
You can't play PlayStation games on the Internet, but if you have a PlayStation 3, you can go on the PlayStation network and play with other people through the Internet.
No you can not
You can not play PlayStation 3 games on a PlayStation 1, but you can play PlayStation 1 games on a PlayStation 3. All of the PlayStation consoles are backwards compatible.
You can play many more than 2 PlayStation 3 consoles in the same room and they do it at the Electronics Conventions all the time. If you can not do it in your home it must be your internet connection capacity. You do of course need a TV for each PlayStation 3 as they both can not play on the same TV at the same time offline or online
7 people can play at once on certain games
Playstation 3 same if your talking about the PS2
You cannot play Playstation 4 games on a Playstation 4 console. You are also unable to play Playstation 3 games on the Playstation 4.
you can only play playstation games on PlayStation 1, 2 and 3
no
no
no
no