noun / verb
code
A system of symbols representing information or instructions.
She types a line of code on her computer.

Etymology
Latin codex named a book, including a compiled body of rules. Code extended the idea of an organized system to sets of symbols and the rules for interpreting them.
In context
letting agents and landlords need a clear and unambiguous code and this amendment is a sensible addition um to the bill which will strengthen the private rented sector
More examples
- This code tells the computer how to sort names.
- They use a secret code to exchange messages.
- Each package has a code that identifies its destination.
- We code survey responses by topic.
Forms
code · codes · coded · coding
coder noun — A person who writes computer programs.