of variable • Use explanatory variables • Avoid Mental Mapping • Use searchable names • Don't add unneeded context • Use meaningful and pronounceable variable names • Use default arguments instead of short circuiting or conditionals
Side Effects • Don't write to global functions • Function arguments (2 or fewer ideally) • Functions should do one thing • Function names should say what they do • Functions should only be one level of abstraction • Remove duplicate code • Set default objects with Object.assign • Don't use flags as function parameters
specific steps used to achieve the desired results — the flow control: How to do things. • Declarative programs abstract the flow control process, and instead spend lines of code describing the data flow: What to do. The how gets abstracted away.