Creating vim split window with arbitrary content

What: Create a split window in Vim with arbitrary content
Why: Displaying information easily along text your are editing
How: Use Vimscript

A simple Vimscript script

Create a file test.vim with the following content. It defines a function which creates a new buffer, adds text to it and show it in a split window on the right.

Use the defined function

There are multiple ways, the function can be used. You can create a plugin (see https://learnvimscriptthehardway.stevelosh.com/chapters/41.html) or call the function from within Vim: