The Internet has been a huge boon for information-seekers. In addition to sites maintained by newspapers and other traditional news sources, there are untraditional sources ranging from videos, personal Web pages and blogs to postings by interest groups of all kinds — from government agencies to hate groups. But experts caution that determining the credibility of online data can be tricky, and that critical-reading skills are not being taught in most schools. In the new online age, readers no longer have the luxury of depending on a reference librarian's expertise in finding reliable sources. Anyone can post an article, book or opinion online with no second pair of eyes checking it for accuracy, as in traditional publishing and journalism. Now many readers are turning to user-created sources like Wikipedia, or powerful search engines like Google, which tally how many people previously have accessed online documents and sources — a process that is open to manipulation.