The Users component handles who can get into a site and what they can do once they are in. On the front end it provides registration, login and logout, profile editing and password recovery. In the administrator it is where accounts are created, blocked and managed, and where user groups and access levels are defined.
Access control in Joomla works by placing users into groups and granting permissions to those groups, rather than to individuals. Alongside that, Joomla includes account-security options such as multi-factor authentication and passwordless sign-in, and an actions log for auditing what was changed and by whom. Users documentation
Note that some of the user views will not display anything unless you are logged in to the site.