They impact our lives in myriad ways, sometimes visibly, sometimes not. They also raise many social and personal issues worth considering. Now it is possible to communicate with people whose faces you've never seen. These relationships may be based on shared interests or hobbies or focus on games that you both like to play.
Some people even prefer to communicate by computer rather than in-person.
They allow for easier, faster and cheaper collaboration among colleagues who live in different places. Sure, people sometimes photocopied a few pages for their friends, but they were not able to give away hundreds of copies without incurring large expense. But with the ease of publishing electronically, particularly on the Internet, it is much easier to copy other people's work and even claim it as your own. The First Amendment guarantees freedom of speech within a set of guidelines determined by legal precedent, but this amendment is being challenged as networks make it easier for pornographers and others to broadcast materials that may be objectionable to some groups but acceptable to others. With books and newspapers, it is hard enough to know whether the information you read is accurate.