If you've worked with databases in the past then it is probably certain that you have worked with PHPMyAdmin. PHPMyAdmin is a great web tool for interacting with your database; however, since it is web based tool it can be kind of slow and the interface a little outdated.
And if you want to use a great desktop app for interacting with your database, Sequel Pro is a great alternative. Sequel Pro makes it super easy to add new databases, add new tables, add new rows, and any other type of database task you can think of. Be sure to download Sequel Pro and try it yourself :)