A hero image is typically an image that is placed prominently on a web page, usually in the front and center of the page. The image will be adapted to show the same on any size of device to be able and convey the same information to all users during the first contact. It is considered the first visual that a web site visitor will see and usually is made up of both an image and a text.
Hero images can be dynamic or static and can be either a product that the site sells or it could be the main story or headline topic of the site. The main goal of any site is to make sure the message they are trying to convey is as clear to all users as fast as possible upon entrance on the site. This is best done by ensuring that the main information is placed in such a way as to attract attention every time.