1) Information on almost every subject imaginable.
2) Powerful search engines
3) Ability to do research from your home versus research libraries.
4) Information at various levels of study. Everything from scholarly articles to ones directed at children.
5) Message boards where people can discuss ideas on any topic. Ability to get wide range of opinions. People can find others that have a similar interest in whatever they are interested in.
6) The internet provides the ability of emails. Free mail service to anyone in the country.
7) Platform for products like SKYPE, which allow for holding a video conference with anyone in the world who also has access.
8) Friendships and love connections have been made over the internet by people involved in love/passion over similar interests.
9) Things such as Yahoo Answers and other sites where kids can have readily available help for homework.
10) News, of all kinds is available almost instantaneously. Commentary, on that news, from every conceivable viewpoint is also available.
Disadvantages:
1) There is a lot of wrong information on the internet. Anyone can post anything, and much of it is garbage.
2) There are predators that hang out on the internet waiting to get unsuspecting people in dangerous situations.
3) Some people are getting addicted to the internet and thus causing problems with their interactions of friends and loved ones.
4) Pornography that can get in the hands of young children too easily.
5) Easy to waste a lot of time on the internet. You can start surfing, and then realize far more time has passed than you realized. Internet and television together of added to the more sedentary lifestyles of people which further exacerbates the obesity problem.
6) Internet has a lot of "cheater" sites. People can buy essays and pass them off as their own far more easily than they used to be able to do.
7) There are a lot of unscrupulous businesses that have sprung up on the internet to take advantage of people.
8) Hackers can create viruses that can get into your personal computer and ruin valuable data.
9) Hackers can use the internet for identity theft.
10) It can be quite depressing to be on the internet and realize just how uneducated so many people have become in today's society.