As a website owner it is vital that you have some way of tracking how well your website is performing. You need this information to ensure that you are investing your time and money in the right avenues of marketing.
With the right tracking software you can easily find out how many people are coming to your site, where they are finding you and what they are doing once they land on your site. This information will allow you to easily see if there are any major issues on a page which may be causing people to leave such as broken links or issues with content displaying correctly.
There are many programs that offer statistic tracking the most commonly used on being Google Analytics. Google analytics is very user friendly and will allow you to personalise it to see the information that is most important to you at a glance. You can drill down quite deep in to the stats and do comparisons for previous periods to see what has been happening.
Web servers often have their own stats software bolted on but these are often quite limited in terms of data and also sometimes record visits from spiders that crawl your site.