Hello, Fatemi127! Welcome to Wikivoyage.
To help get you started contributing, we've created a tips for new contributors page, full of helpful links about policies and guidelines and style, as well as some important information on copyleft and basic stuff like how to edit a page. If you need help, check out Help, or post a message in the travellers' pub. If you are familiar with Wikipedia, take a look over some of the differences here.
I reverted your edit on Persian Gulf. The term "Arabian Gulf" is used, so we should mention it. I did edit to reduce the emphasis on it, though. Please take a look and start a discussion on the article's talk page if you disagree. Pashley (talk) 21:49, 11 February 2014 (UTC)