A form of communication for the market, advertising was considered just to be delivering openly sponsored messages to consumers so as to get them to buy products or services. But as with any field when time passes the field evolves. The field of advertising evolved and grew to include new technologies as well as new creative processes. With Internet in the picture, online advertising became the new thing, it was a subset of advertising that used Internet as its medium.
Online advertising is a vast chasm, bust most of it can be separated into a few categories, such as: