Domain name means a name who recognize a site but the there are approximately 68 million .COM domains registered. That’s a lot of domain names out on the Internet that are either already taken or just parked in some obsolete spot gathering dust and all kinds of age.
There are 900 possible combinations for two letter sequences. If you’re looking for ET then you just won’t find it. Even allowing for digits, again every single web address is taken. Of course, that’s ignoring the fact that .COM registrars now mandate a 3-character minimum length, so it wouldn’t be an option.
Many of the three-letter sequences are taken. Adding digits to a domain name creates a number of garbage domain entries. If you’re dying to acquire great domains and unique domain names, they’ll free up sometimes only to be auctioned off through unique domain name sales.