An HTML counter is a website addition that tracks the number of visitors that come to the website. It is a few simple lines of code, and generally displays as a small ticker somewhere on the page that updates with each new visitor. Generally, an HTML counter does not display any data about visitors, such as what site or search engine brought them to the website. It is relatively simple to write a counter like this, or the lines of code may be downloaded free from sites that offer them; typically this just requires a link back to the original site.
Fewer website designers choose to use an HTML counter now than they once did. This is because most web hosts are now capable of tracking detailed visitor data; not just the amount of visitors, but the amount of unique hits, where they originated from based on an IP address, and how they found their way to the website. Web hosts that provide stats like these may even be able to provide the specific search terms that bring visitors to a site. This is much more useful to most web designers than a simple HTML counter that just shows hits, and cannot distinguish between unique visits or multiple visits in one day by the same person, or even simple page refreshes.
Nonetheless, some web designers do still like to display an HTML counter on the main page of a website that will count each visit. It is generally easiest to simply search online for free HTML counters; these are available in many different designs, and are provided for free from various websites. The website designer only needs to insert a few prewritten lines of code into the HTML for the website, and the HTML counter will then link back to the original website and count visitors.
For those who are more experienced in web design and writing HTML, it is also possible to simply write an HTML counter that does not link back to another website. Instructions for doing this may be found online as well. Both of these types of counters will allow the web designer and the visitors to see at a glance how many people have visited the website, and may be a quick and easy way to track whether certain changes are drawing more visitors to the website, or whether additional changes need to be made.