There’s a basic principle across most of the Microsoft applications, and that’s that if you want to do something to something, then you probably have to select it first. Without that, the app doesn’t know what you want to do stuff too.
Microsoft Word is a great example of the principle in action – if you want to do something to a word, then you need to select that word first. While anyone who’s ever used a mouse can click and drag to select a word, it’s a surprisingky difficult way to do consistently. It’s really easy to drag too far and select the next word or line.
On that basis it’s really useful to have a simple method to select a word that will always work for you.
To select a word in Microsoft Word, just double click the word.