Eli Pariser, author of The Filter Bubble: What the Internet Is Hiding from You, explains how websites from Facebook to Google change our search results to tell us want they think we already want to hear:
“Don’t Bubble Us” is another link concisely summing up these themes. Duck Duck Go is a search engine which does not bubble people’s searches. Personally, I think that the efficiency of bubbles that prevents me (now that I realize it) from having to wade through religious sites I wouldn’t be interested in when I type in “atheism” is a good idea as an option one can select for specific searches. But it should be opt-in, not the opt-out default.