A click on any of those 12 windows will show a list of search sites in the view below. For example, click on the first window. This is a group named 'Books'. This group has some search sites like 'Amazon Books','Barnes and Noble', etc. Similarly the remaining groups have different search sites.
Groups are nothing but a set of search sites.
By default, Talash ships with a set of 12 groups like 'Music', 'Books', 'News', 'Search Engines' 'People', etc. Different search sites are added to these groups. For example, 'Amazon Books','Barnes and Noble', etc are present in 'Books' group, while 'Amazon Music', 'Borders Music', etc are present in 'Music' group and so on. Talash allows you to customize your own group. You can create your own group.