Networking is an essential skill for every individual, but at the same time it is never explicitly taught to most individuals. Networking is all about making connections with people, developing relationships that can be utilized for personal gain down the line. When one is looking for a job, the odds of getting hired go up significantly when someone the employer trusts recommends you. Recommendations are essential to get ahead or even to get hired for many jobs or get into graduate schools. Favors that others owe you, possibly from doing favors for them, can be very useful when called in at the right time.
As important as networking can be, it should not be the central motivation for developing relationships. People can often tell if you have an ulterior motive behind your actions, so either be upfront with your intentions or be genuinely interested in the other person.