Functionality
Unlike straightforward web browsers, Opera Mini fetches all content through a proxy server and reformats web pages into a format more suitable for small screens. A page is compressed, then delivered to the phone in a markup language called OBML (Opera Binary Markup Language), which Opera Mini can interpret. The data compression makes transfer time about two to three times faster, and the pre-processing improves the display of web pages not designed for small screens.
By default Opera Mini opens one connection to the proxy servers, which it keeps open and re-uses as required. This improves transfer speed and enables the servers to quickly synchronize changes to bookmarks stored in Opera Link.
The Opera Software company maintains over 100 proxy servers to handle Opera Mini traffic. They run Linux and "are massively parallel and massively redundant."
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