Opera is the RC Cola to Coke and Pepsi. The L.A. Gear to Nike and Reebok. The one with the hairy hairy chest to the worst and best. Opera has always found itself as a third-place browser since the Netscape vs. Internet Exporer browser wars.
Originally, Opera was an ad-supported shareware browser, but became completely free in order to complete. The mobile version keeps the revenue flowing in for the company.
Opera markets itself as the fastest Web browser, and has supported tab-browsing before its competitors.