Question

what are templates ? How are they useful?​

Answer 1

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A template is a file that serves as a starting point for a new document. When you open a template, it is pre-formatted in some way. 

Templates used as a guide to making something. Here are some examples: A ruler is a template when used to draw a straight line. A document in which the standard opening and closing parts are already filled in is a template that you can copy and then fill in the variable parts.

Answer 2

The idea behind the template is that it is a guide or model that can be reproduced. When it comes to Office, templates are basic documents with some elements like formatting and even content in place. Their main purpose is to help you get started, or take the time out of beginning certain tasks.