If you search for [python] on Ask.com and Google, you will see Google has the first 10 results about the programming language called Python, while Ask has a one-box results that features a picture of a python (snake) and a definition and also alternates results about the two meanings of the word.
Of course, most of the pages that contain the word "python" will be about the programming language (you can check that, searching for [python snake] that gives 2,310,000 vs 234,000,000 results for [python]). That's why Google will consider these pages the most relevant. In fact, none of the first 100 results for [python] in Google is about the snake (few of them are about Monty Python).
Ask.com uses ExpertRank, finds clusters for the query you entered and returns the most authorative sites for each cluster.