The most basic expressions in Scaly are literals. A literal simply returns a value that is written literally into a program. So our first program is not the famous Hello World version in Scaly (which comes later because it is obligatory), instead we write up the shortest non-empty Scaly program imaginable:

0

Use your favorite text editor and type that lone zero digit into a file, give it a name like shortest.scaly, and compile it to an executable. As you might expect, the program does exactly nothing useful. Immediately after startup, it returns a 0 value to the operating system just to indicate that everything went fine. If a program is to return 0 as the last action at the end of it, that 0 literal can be omitted. That’s why the shortest Scaly program actually is the empty program which contains nothing and does exactly the same as the above version - just returning 0. Try it by deleting the zero digit, compiling and running the program.

There are also string literals like "Hello World!", the two bool literals true and false, and more.