The first thing to investigate after a major dip in traffic is your website itself. Is it actually working? Is there a problem with the domain? Mechanically, is everything functioning as it should? If all that checks out, make sure the critical inbound links are still intact. If the majority of your traffic comes from inbound campaigns, ensure your inbound marketing platform is working properly. - Jeffrey Kamikow, Cross Audience
Web analytics is the measurement of the behavior of visitors to a website. In a commercial context, it especially refers to the measurement of which aspects of the website work towards the business objectives of Internet marketing initiatives; for example, which landing pages encourage people to make a purchase. Notable vendors of web analytics software and services include Google Analytics, IBM Digital Analytics (formerly Coremetrics) and Adobe Omniture.