Start

The Start part is the front door of Musi Book. It does not try to teach every feature at once. It teaches the first reading habit: a file contains named declarations, and each declaration gives the next reader a stable thing to talk about.

Begin here even if you already know another language. Musi uses familiar words such as let, function, block, and mutation, but the way those pieces fit together is easier to learn in this order. The first few chapters keep the program small enough that you can run the example, read the result, and still remember every name in the file.

A good first pass through this part feels like walking through a small workshop. Getting Started shows the tools on the bench. First Program gives you one useful object to make. Reading Musi Code teaches how to scan the labels before worrying about every symbol. Values and Let teaches how to name the pieces. Blocks and Expressions show how several steps become one result. Mutation comes last because changing state is easier to understand after stable values feel ordinary.

Use modest examples: a grocery list, receipt line, pet profile, or appointment reminder. The point is not the domain. The point is learning how a Musi file explains itself.

After this part, you should be comfortable with three questions: what names are introduced, which names are public, and what value each expression returns. That is enough structure to move into the rest of the book.