here is the number one rule to be safe :

If somone wants your password , threatens to hack you , tells you to use your log in information on an other site , IGNORE THEM , they cannot hack you or boss you around , no one , I repeat NO ONE has the athaurity (pardon my spelling) to ask for your password , if they are a part of steam , they don't need to ask for your password , alot of "people" (i prefer the term "no lives") may give you a link to a site asking you to login with your steam username and password , DONT EVEN THINK ABOUT PUTTING IN YOUR INFO!! , the only site you log into is the main one , even if theres another site that looks alot like steam , its a proffessionall no live made site , thank you for reading ;D