Wikipedia useful or not?

Wikipedia is a site that we all have come across at least once in our lifetime. We have used it as a site to direct us in the questions we have. Yet how reliable is this site? Although it is a site that has a lot of valid and useful information it carries. People have used it as a reference in papers and in other projects as students, so how credible can it actually be? The fact that it allows people to go on and edit what is going on with that topic, how can you tell if what the people are saying on the site to be true? A lot of questions come up with the topic of Wikipedia, because some people are not able to differentiate between what is true and what is false. Some people can be opinionated on the subject at hand that can be very offensive to other people. When writing people are have to allow themselves to be very middleminded when writing.