What are the domain-name rules?

[cooper smith]

I'm looking for a domain name for my website, and I'd like some advice on how to choose one.

[Clara Smith]

Some of the rules to be followed are as follows:
1. Only letters, numbers, and hyphens are permitted in domain names.
2. Hyphens are not allowed at the start or end of a domain name.
3. A domain name that is already in use is not available.
4. Domain names are not case sensitive.

[Jamie Lee]

Use the appropriate domain name extensions (.com,.org, etc.) Brandable Over Generic.

[Milo Adey]

It Is Better To Be Short Than It Is To Be Long.