Lists of notable question and answer websites are posted on RefSeek.com, FreeMake.com and GuidingTech.com. Popular question and answer websites include Answers.com, Quora.com, Ask.com and LinkedIn Answers on LinkedIn.com.
AllExperts.com is the oldest and largest free online question and answer service, with over 2 million questions answered as of 2015. Categories include business, travel, education, industry, hobbies, teens, gadgets and people/relationships. A large team of volunteers made up of engineers, doctors, lawyers and scientists answer questions posed by users. Users can browse answers alphabetically or by category and can search specific questions and answers in the search bar on the top right of the page.