A domain is the unique name that lets people find your site among millions of others. It is a virtual address on the internet. Besides letters, it can include numbers and a few symbols.
Long names and too many domain parts are awkward to use. A good domain often includes the company name or the field you work in. If the name you want is taken, add a regional code or a short extra word — keep it clear, and do not overload it with characters.
Say it out loud and type it: is it easy on the phone and on a keyboard? Does it reflect the business, the products, or the services? If yes, that is a solid domain.