ELI5: Explain Like I'm 5

Template processor

A template processor is a piece of software that is used to build webpages and other documents. It looks at parts of a webpage or document and replaces them with information that you give it. For example, if you have a template that contains a list of names, you can use the template processor to replace those names with your own list of names. This makes it easier and quicker to build a webpage or document that has the same structure and layout but with different content.