Opera is most certainly one of the most secure browsers available, and that too for free. It incorporates strong encryption, Secure Shell Layer (SSH) and Transaction Layer Security (TLS) for transferring data, authentication to avoid scams like phishing websites, certificate detection to check for expired security measures, among many more.

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The features and functionality listed above are all part of the default settings in Opera, and they are all instrumental in Opera’s secure web browsing experience.
For websites that should have secure logins and sessions, Opera displays a small padlock next to the address in the display bar. This icon indicates that the website is secure, and that the information the user enters is not privy to prying eyes. It would be extremely unwise to enter any data in online banking sites, for example, without checking for the icon first.