Opera Help and Support

Encryption is a way of scrambling information so that only a legitimate recipient of that information can make it readable again. The most common form of encryption today is public key/private key encryption. Imagine a strongbox that has two keyholes and two separate keys. If you lock the box using one key, you can only unlock it with the other.Security protocolsHovering the padlock icon when visiting a secure server, you will see a string of text that looks something like this: TLS v1.0 128 bit C4 (1024 bit RSA/SHA)The first...

Opera is designed with the most advanced and widespread security measures available, making on-line purchasing simple.Some sites may greet you with a page saying something along the lines of "You do not have a secure browser; please download Netscape Communicator or Internet Explorer." The site designer may, mistakenly, believe that only those browsers support advanced security, although Opera has levels of security that are as good as or superior to these browsers.Changing how Opera identifies itself will often allow you to...

The settings in Preferences > Advanced > Content allow you to set up external applications that Opera can use to enhance your browsing experience.Plug-insPlug-ins are external applications that Opera can use to display images and video clips, show files, or play sounds that the browser is not able to handle by itself. Some of the most popular plug-ins are Macromedia Flash, QuickTime, and Adobe Acrobat.Plug-ins are essentially separate applications. Therefore, Opera's various security settings will have no effect on how...

Downloads and File TypesOpera handles a large number of varying file types, including HTML files, graphical files such as JPEG and GIF, and other types of files which it cannot use by itself. These include PDF documents, word-processor documents which can end in SXW, RTF, DOC, or any of a dozen other extensions. For certain file types, Opera needs multimedia plug-ins.Configuring settingsBy default, Opera will determine how to handle a file by its MIME type. MIME types are descriptions used by Web servers to identify files to...