The XL Toolbox is written in Visual Basic for Applications (VBA), the programming language that is built into the Office applications. When I started to create “Daniel’s Functions”, the predecessor of the XL Toolbox, using VBA was the logical choice: It came with Excel for free, and BASIC is very easy to learn. In the early days, I wrote computer programs in BASIC on the Commodore C64, and later moved on to Turbo Pascal on an IBM PC. Thus, the learning curve for VBA was not very steep.
This is a companion discussion topic for the original entry at https://www.xltoolbox.net/blog/2013/12/selecting-the-right-tool-for-the-toolbox.html