Opera 42.0.2393.137 - Quick and safe web-browser from Opera Software. Opera has a very low system resource usage, and provide very fast pages loading, even on slow connection.
Opera has a built-in download manager, that can be opened in a new tab. In latest version of the browser there is no Bookmark anymore. Instead, you have a Express panel with a most visited web-sites, and Stash - it lets you to save interesting pages and read it later. With a Opera Link you can sync data between browsers, installed on different computers.
Also Opera has some useful tools for web-developers, like Element inspector and page`s source code viewer.