This area in the graph again depicts combined share of searches at InfoSpace and Lycos. InfoSpace runs meta search engines, which get search results from a variety of search providers while Lycos.com primarily provides access to paid inclusion listings from LookSmart, unpaid listings from Yahoo and paid listings from Google and Lycos's own internal program.
Lycos-owned HotBot primarily provides access to Yahoo powered listings. Some additional "Mix" traffic is likely contained within the other slice, but this is impossible to break out.

Others include those shares of searches from other sites that use their own technology or editorial processes. The search result includes some share that belongs to the other provider categories.