Online advertising is all about getting your website in front of the people who are interested in your product or service. There are a number of different ways in which a website can get itself advertised on the web like contextual ads on search engine results pages, banner ads, Rich Media Ads, Social network advertising, online classified advertising, integrating pop-ups on a visited site, advertising networks, and email marketing, including email spam. In most cases it will prove preferable to include a variety of types of media and different versions of online advertisement.Search Engine Advertising is a method of placing online advertisements on Web pages that show results from search engine queries based on keywords and phrases entered by internet users or potential buyers. The three biggest sources of this type of advertising are Google, Yahoo. Search engine advertising works on the simple principle of supply and demand.Contextual Advertising, also known as content-targeted advertising is based on keywords in the surrounding content or context, which means that your advertisement is shown on a Web site that is ‘in context’ to your specific product or service. This advertising technology works by publishing your text or rich media advertisement on the relevant affiliated Web sites that best match your selected targeted keywords or channels. This is usually less profitable than search advertising which is based on user intent expressed through their keywords.There are three common methods of purchasing online advertising space for various types of advertising tools:* Cost Per Click also referred to as the Pay Per Click means that payment for advertising is proportional to the number of unique clicks on advertising banners. Cost Per Click differs from Cost Per Visit in that each click is paid for regardless of whether the user makes it to the target site. Either a flat-rate or a bid-based pricing scheme one can choose from for a Cost Per Click ad. A drawback to the Cost Per Click advertising model is that it can be compromised by click fraud.* Cost Per thousand impressions means that the method of payment is based on the number of views. This advertising model is generally reserved for websites with high traffic volume (more than one million pages viewed per month). The total price paid in a Cost Per thousand impressions deal is calculated by multiplying the Cost Per thousand impressions rate by the number of Cost Per thousand units. For example, one million impressions at $10 Cost Per thousand impressions equal a $10,000 total price.* Cost Per Action or acquisition, also be known as or Cost Per Lead means that payment is based on performance, and is a common method in affiliate marketing programs. In this advertising scheme, the publisher takes all the risk of running the ad, and the advertiser pays only for the amount of users who complete a transaction, such as a purchase or sign-up. According to industry observers, this is the best type of rate to pay for banner advertisements and the worst type of rate to charge.Online advertising is so flexible and cost effective that even small businesses can afford to look into advertising online as in many types of ads there is no pay unless there are results. This type of strategy can make advertising very cost effective, especially for those who do not have large advertising budgets. Online marketing services are incomplete without online advertising, without the powerful advertising marketing can never be successful.In this world of businesses the need of online advertising company is crucial. An online advertising company can play a major role in assisting its client companies advertise their products on the Internet and reach their target audience. The future of online advertising and online advertising companies looks bright and very exciting to be sure.