Wikipedia gets frequently slammed by critics. As a final authority it can be problematic. This is due to entries being available for editing and amending. However, this is a good go-to starting point for research and for those who just want to understand a topic a bit better. The external links as well as the bibliography are wonderful as you branch out into other sources.

It's just what it says: another search engine for my firefox to use, allowing me to search english wikipedia with a customizable prefix. It's nice to have such functionality because english articles are usually bigger and better than polish, and the polish version of firefox only comes with a polish wikipedia search built in.