Functional programmers use functions to write code in small, self-contained chunks. Writers can Write small, self-contained notes.

There are different reasons to create a new function:

• Break up a large and unmanageable one.
• Avoid duplication by create a dedicated function for an common operation that would otherwise be repeated in multiple places. This helps one focus on creating a single, well-written implementation of the code.
• Create a stub implementation. You may write the name for a function that you haven’t yet implemented, since you know you’ll need it, but don’t want to write it yet. The case of writing is a bit different from code, since the programmer usually knows what needs to happen, and then needs to figure out how to do it - they need to write the implementation. In the case of writing, one sometimes knows what to say, but not yet how to say it. That is like the programmer. But sometimes, while writing, you may just have a question, and have no idea where it leads. You could be making an argument, and maybe wonder if it is correct. In this case, you could continue writing the present note, create a stub note for the question you want to turn to next. This again helps you work on just one small idea at a time.