> whatever usage we’re talking about is by definition previously mentioned Nope, I have to disagree. "The usage" can mean a usage mentioned elsewhere out of th

> whatever usage we’re talking about is by definition previously mentioned Nope, I have to disagree. "The usage" can mean a usage mentioned elsewhere out of the context of the current text or discussion. "ls is used to list files, the usage has various flags to manipulate its behavior", now if you add aforementioend before usage there that means more details about what the usage is and how to find that out might have been mentioned before this sentence. Otherwise you will have to read the whole text or presume you have to search the usage details elsewhere. This is very useful when talking about a subject that is very new to the audience or when making a case for something. An obvious question about the following phrases can be answered by directing users to already mentioned content that can address their questions or doubts.