Search Engine Marketing (SEM), which is marketing a website online via search engines, either by improving the site's natural (organic) ranking through search engine optimization (SEO), buying pay-per-click (PPC) ads or purchasing pay-for-inclusion (PFI) listings in website directories, which are similar to offline yellow page listings.
Email marketing, which is a method of distributing information about a product or service or for soliciting feedback from customers about a product or service through Email. Email addresses of customers and prospective customers may be collected or purchased. Various methods are used, such as the regular distribution of newsletters or mass mailing of offers related to the company's product or services. Email marketing is essentially the online equivalent of direct mail marketing.
Banner advertising, which is the placement of ads on a website for a fee. The offline equivalent of this form of online marketing would be traditional ads in newspapers or magazines.