Opera is a multi-platform web browser developed by its namesake company Opera. The current edition of the browser is based on Chromium. Opera is available on Windows, macOS, Linux, Android, and iOS (Safari WebKit engine). There are also mobile versions called Opera Mobile and Opera Mini. Opera users also have access to Opera News, a news app based on an AI platform.

Opera was initially released on 10 April 1995, making it one of the oldest desktop web browsers still actively developed. It was commercial software for its first ten years and had its own proprietary layout engine, Presto. In 2013, it switched from the Presto engine to Chromium. In 2016, Opera, developed in Norway, became a subsidiary of an investment group led by a Chinese consortium. In 2018, Opera Software went public on the NASDAQ stock exchange. By the end of 2022, the consortium sold all of its shares, and Opera in turn committed to repurchase all of its American Depository Shares to reestablish its corporate autonomy.

The company released a gamer-oriented version of the browser, Opera GX, in 2019, and a blockchain-focused Opera Crypto Browser into public beta in January 2022. In April 2023, the company announced a major overhaul to the browser called Opera 100 and code-named "Opera One", adding a new user interface and several AI-related features. Opera 100 was released on June 20, 2023.