A domain is a unique naming system that allows the identification of a website or an email address on the internet. A domain name is used to understand and remember a web address. For example, access to a website can be provided using a domain name like "www.deneme.com".

Domain names allow IP addresses (Internet Protocol addresses) to be expressed in a more understandable and easy-to-remember format. IP addresses are numerical labels assigned to each internet-connected device, giving them a unique identity on the internet. In contrast, domain names consist of easily understandable words that correspond to these numerical IP addresses, making it simpler for people to navigate and remember websites and services on the internet.

Domain names consist of two parts. The first part can be a prefix like "www" or a subdomain like "mail" and usually represents a particular service or server. The second part consists of a main name (domain name) such as "example" and an extension (top-level domain) such as "com". Extensions are codes assigned to different categories and geographic regions, such as ".com", ".net", ".org", ".edu", and ".gov".

The registration and management of domain names are carried out by authorized domain registration organizations (domain registrars). Users make agreements with these organizations to register a domain name and obtain the right to use it for a specific period (usually one year).

Domain names have numerous benefits, such as branding, creating an online presence, facilitating website access, and establishing a professional image. Choosing the right domain name can strengthen the presence of a business or individual on the internet and enhance interaction with their target audience.