Craigslist primarily serves as an online classifieds section where users can post and browse advertisements relevant to their local areas. It also offers discussion forums that cover a variety of topics and interests.
Browsing Craigslist is free and requires no account. Posting ads on Craigslist requires no account, and it is also free with some exceptions. As of 2015 there are fees for posting job listings in most major metropolitan areas. There are fees for advertising brokered apartment rentals in New York City. There are also fees for advertising therapeutic services and for dealer listings of vehicles and tickets in the United States.
Free categories to post in include Housing, Personals and For Sale. Postings can include user-uploaded pictures. Users can post anonymously, and to facilitate this, Craigslist offers a two-way email relay service. Ads that use this service include a randomly generated craigslist.org domain email address. Craigslist automatically forwards mails sent to this public address to the poster's private email inbox. A poster can reply to these emails directly without revealing her email address; the relay service forwards the poster's replies. In addition to allowing posters to remain anonymous, this service also protects them from spam.
Posting in some Craigslist forums requires creation of a free account.