A domain is your identity online. It separates you from everyone else - once yours, as long as you keep renewing it, no one else may have it.
There are two parts to a domain – the domain name itself, and the TLD (top level domain) extension. The most popular TLD is the .com extension – it is synonymous with online business. But due to its popularity, getting a good domain name with '.com' is hard - most have been bought and are not available.
Most TLDs have a meaning behind them - .EDUs are used by educational institutes, and .ORGs are supposed to be used by non-profit organizations. A domain with a TLD of 'com.hk' is very likely Hong Kong-based. There are other TLDs too, such as .cc, .tv, and .us. These are all associated with either a company or with a country.
Many hosts will register a domain for you if you do not have one (it must be available though). You need to be careful that the domain is registered in your name and not theirs.
International Domain Names (.com /.org /.net)
Once the domain name is expired, the service related to the domain name will be suspended immediately. You'll need to pay the renewal fee in order to reactivate the domain name, and it takes around 24 hours. If the domain name is not being renewed within 30-60 days after expired, it goes to a "grace period" means no one can renew nor register the domain name. After the "grace period", the domain name will be released to public again.
