Quote:The good news is that Twitter implements industry-current security standards reasonably well, especially in terms of password storage. If your account was compromised, then Twitter may have leaked a "salted hash" of your password.
Some background: a hash is a one way function: you can manipulate a plaintext password into a hash, but you can't reverse the process and go from hash to password. Thus if a bad guy has a table of hashes, the only way he can get the passwords is to hash a dictionary of possible passwords and compare his hashes with the stolen hashes.
Twitter uses bcrypt to hash passwords, which is secure in its slowness -- it will take the attacker a long time to crack a single salted hash. The fastest hardware on the market will crack a password salted/hashed with bcrypt once every 12 years. For a site with millions of passwords, a meaningful attack is utterly impractical unless some theoretical flaw is found in bcrypt itself.
So your passwords are actually reasonably safe if the attacker only has the hash they stole from Twitter. But there's significant portion of the internet that does not have a modern security policy. This includes sites that store your password in plaintext -- the attacker doesn't have to do any cracking at all. This is why you need to use different passwords for the various sites you use. If one site with a weak password policy gets owned, you risk your entire digital identity. (This is especially true for email. If you register with a website using your email and the same password you use for that email, then you are taking a huge risk. If I get your email account then it's game over -- every other account is a "reset password" away from being mine.)
tl;dr Use different passwords for the sites you use, and never register for a site using your email address and email password.

(Feb 8, 2013 12:36 PM)Eternity4ever Wrote:  IMHO, facebook & twitter just a waste of time & I still wonder why people gather there Instead of focusing on learning something.