Access information about domain name statistics at Zooknic.com Internet

Access information about domain name statistics at http://www.zooknic.com/Domains/counts.html

1.gTLD is an abbreviation for what word(s)?  (Hint: Click on gTLD to answer this question.)

2.What is the number of domain names   worldwide?

3.How many .com names are there?

4.List the extensions that are used with domain names.