@war child,
war child wrote:i have few questions for the computer geniuses out there
1- a friend of mine on facebook has for example 10 mutual friends, but when i open the mutual friends list, only five show, can he hide friends we have in common ?
2-how to remove timeline from facebook ?
I'm Facebook illiterate, but can help with 3 through 5.
war child wrote:3-does opening facebook in https:\ really prevent your account from being hacked ?
If someone were in a position to view the stream of data between your computer and Facebook, then "https" would prevent them from viewing that data. Such data would include both your password, and any information that appears on the pages you are viewing.
That would probably not prevent hacking (which would almost certainly use other means), but it is still a good idea.
war child wrote:4-i gave a friend of mine my e-mail pass and facebook pass, so he can maximize the security on them, if i change the password of both accounts facebook and e-mail, can he still manage to open them ?
It probably depends on how easily he can guess your new passwords. It might also depend on whether he has learned the "Forgot My Password" security question/answer that websites seem to always have.
war child wrote:5-how to prevent your e-mail and facebook from beeing hacked ?
Use long and complicated passwords. And don't give them out to anyone.