In publishing for example, a template is a layout made by someone else to give an idea what to write in different parts of a book or story. A simple publishing template can have spaces for the words, for pictures, for the story title (name), and for the name of the publication.
Humans or machines can use templates. Some computer programs that work with the Internet use a template to separate the way the program works from the way it shows the words and pictures. It can be a way to copy words and pictures. In computer programming, templates save time because the programmer does not need to write the same words over and over.
When doctors plan to give a person a new bone joint made of metal or plastic, they can use a template in the shape of the new joint. This type of template is put on an x-ray picture of the person to help to decide the size of joint needed.