A
domain name identifies a site, while a
subdomain is a name placed before a domain that its owner can control. A login page can show a trusted brand in the address without belonging to that brand.
Example you can check
accounts.example.com is a subdomain under example.com.
example.com.login-check.test belongs under login-check.test, even though it starts with example.com. The host ends before the next slash; words in a path or a logo do not establish ownership. Some real domains have multi-part endings, so avoid a simple 'last two labels' shortcut.
What to do with this
Expand the browser address bar and compare the host with the provider's known address. If unsure, open the app or a saved bookmark instead. Mozilla's
domain-name guide explains the naming structure. Our
step-by-step URL check shows the decision in context.
Practical distinction
A subdomain is not automatically suspicious. Many real services use one. The check is whether the complete host belongs to the provider you meant to visit, not whether the address contains a familiar word somewhere.
