The second level domain is the part of the domain name located on the left side of the dot. That on the right is already a top-level domain or, in other words, a domain extension. For example, the name of the site looks like this: regery.com, regery is a second-level domain, com is the first.
To better visualize what a second-level domain is, we give an analogy. A person has a first and last name. The surname emphasizes his connection with the family, clan, that is, a certain group. The name, on the contrary, distinguishes it from the family, emphasizes individuality. That is, John Smith is a unique John and a representative of the Smith clan at the same time. Also with sites, regery is the first name, com is the last name.
Domains are organized with a specific hierarchy. They consist of parts called levels. These levels are highlighted with dots.
Each second level domain must be unique. This is a prerequisite for registration. The domains banana.biz and banana.com are not the same thing, as they are registered in different domain zones.
Buy a second-level domain can individuals and legal entities. Usually registration takes place in a free form and no additional documents, except for a passport, need be presented. Although for some areas there are restrictions.
Short and long combinations can be used. There is no special difference. But users better remember short names, so do not overdo it with the number of characters.
Registration of a second level domain, as a rule, occurs instantly. The name is checked for uniqueness and compliance with the requirements of the selected coverage area. Names are registered for a certain period - usually for a year. When the expiration date, the domain can be renewed for a fee.