A domain name is a human-friendly address, sometimes called a URL (Uniform Resource Locator). The internet works on IP (Internet Protocol) addresses. These are numbers, much like a telephone number. However, most people find it much easier to remember names rather than strings of numbers. Like all companies, TechSolutioNZ choose to publicise their domain name (https://techsol.co.nz) rather than their IP address (http://50.87.153.111).
Your domain name is unique to you. When someone types it into an Internet browser (e.g. Internet Explorer or Mozilla FireFox) they'll be taken directly to your space on the Internet where they can view your site or files.
Domain names also have other uses. For instance, when choosing an email address, rather than having joe.bloggs.384574@myisp.com you could have joe@mydomain.com. This is far more memorable, and also means that if you decide to change your ISP you won't have to send out emails telling people your address has changed.
