Search allows users to easily find a user, topic, event, basic page or group. The search function can always be found in the header menu.
When searching using the search icon in the header menu, real-time search suggestions are provided. You can read more about this here.
On the search results pages, the ALL tab shows all relevant results, and users can narrow down their search via the tabs 'content', 'users' and 'groups'. These tabs also contain a few filters, like interests, expertise, content tags, profile tags, etc.
Regular users are able to search for other users using both their name and username. When a nickname is enabled on a user profile, regular users can also search for users using their nickname.
Site managers are able to search for users using their email address as well.