What is the difference between a directory and a search engine?
The difference between a search engine and directory is the way websites get entered into their index. People submit their sites to the directories, which are reviewed by human editors. Think of the directories as collections of internet sites organized by subject. Search engines work by sending out a spider to fetch as many documents as possible. Following, another program called an indexer, reads these documents and creates an index based on the words contained in each document.

The organic search results (natural search results) occupies the largest part of the search results pages. By default, Avasearch will display 10 organic search results per page. These will be displayed below the sponsored advertisements should there be any, if Google's algorithms find them qualified for the same or similar search query. Organic search results are also based on Google's algorithms but are filtered according to Avasearch’s indexing criteria. Read more about Avasearch’s indexing criteria here.

Sponsored results (Ads by Google) are displayed at the top and right hand side of the page. Sponsored results are being paid to Google by their advertisers. Although Sponsored results do not follow the Avasearch filtering, Google’s approach to ads is similar to its approach to search results: the ads must deliver useful links

What does the AVA (AVASERCH) stands for?
AVA stands for avant-garde

According to the freedictionary.com:
a·vant-garde (ävänt-gärd, vänt-) n. A group active in the invention and application of new techniques in a given field, especially in the arts. adj. Of, relating to, or being part of an innovative group, especially one in the arts: avant-garde painters; an avant-garde theater piece.

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