The Header is the very top section of the website page which contains the logo and navigation.
The Header can also contain some additional information like an email or phone number, and some functionality like social icons that link to the social media sites, a Google Search box to search for information within the website or a button (to shop, contact, donate, etc.).
The Header is repeated on every page of the website (with the exception of a Landing page, which may exclude the navigation).
Here are some representative examples of how a Header can be designed and configured: