Opera is a web browser and inter-platform Internet software package. Opera consists of a collection of software for the Internet such as web browsers, as well as software for reading and sending e-mails. Opera is made by Opera Software based in Oslo, Norway. Opera can run on a variety of operating systems, including Microsoft Windows, Mac OS X, Solaris, FreeBSD and Linux.

Opera is known for having many features that were later adopted by other web browsers. Despite having various advantages, Opera only gets a small share of the market for personal computer browsers around the world. However, Opera has a larger market share in mobile devices such as mobile phones, smart phones, and personal digital assistants. Various Opera editions can be used for devices that use Maemo, BlackBerry, Symbian, Windows Mobile, Android, and iPhone operating systems, as well as Java ME. About 120 million cellphones have been marketed with browsers Opera in it. Opera is the only commercial web browser available for Nintendo DS and Wii. Some televisions have the Opera browser in the set-top box or the settings box. Adobe Systems has Opera technology licensed for use in the Adobe Creative Suite.

Opera presents built-in tabbed browsing, ad blocking, fraud protection, download managers, BitTorrent clients, search bars, and web feed aggregators. Opera also comes with an e-mail client called Opera Mail and an IRC chat client built in.

Opera has the "Speed ​​Dial" feature, which allows users to add up to 25 links (or more, by editing the speeddial.ini file) which is displayed in thumbnail form on the page when a new tab is opened. Thumbnails connected to pages are automatically generated and function for visual recognition on speed dial pages or can be changed using Opera Image Dial Generator. Once set, this feature makes it easy for users to navigate to the selected web page.