A web counter or hit counter is a computer software program that indicates the number of visitors, or hits, a particular webpage has received. Once set up, these counters will be incremented by one every time the web page is accessed in a web browser.
The number is usually displayed as an inline digital image or in plain text. Image rendering of digits may use a variety of fonts and styles; the classic example is the wheels of an odometer. The counter is often accompanied by the date it was set up or last reset, without which it becomes impossible to estimate within what time the number of page loads counted occurred. Some web counters were simply web bugs used by webmasters to track hits and included no visible on-page elements.
In one SEO spamming technique, companies pay to have their site listed in the HTML code of a free hit counter. Thus when a user puts it on their page, a small link will appear at the bottom and can be a quick way for sites to accumulate inbound links. This is often performed by sites in very competitive web fields like online gambling. In 2008, Google removed a number of high-ranking mesothelioma sites that had been using counters from the top results.