Functions

Naming functions generally share a lot in common as naming variables. Though, given that functions do things, a good practice when naming them is to use verbs.

function createUser(name) { ... }

If the function returns a true or false value, the tip from variables applies.

function isUserActive(user) { ... }

Get/Set

A very common habit is prefixing function names with get for retrieving values and set for assigning values. It aligns with the namin convention but I would still label it as borderline bad practice.

function getUserById(id) { ... }
function setVerticalPosition(value) { ... }

I would encourage people to find a better verb than get or set if they can help it. If those are truly the best verbs to use for a particular function, then by all means.

function retrieveUser(id) { ... }
function raise(value) { ... }