``` function functionName [parameterList] statements end functionName ```
The function keyword defines a new function handler of the specified name. You call a function by placing parentheses after its name, enclosing any parameters within the parentheses:

get deleteSpaces(" hello ")

The optional parameterList lets a function handler receive values sent along with the function call.

When a function is called, HyperCard evaluates each item within the parenthetical list following the function's name. When the handler begins to execute, HyperCard assigns each value to a parameter variable in the parameterList.

Use the return keyword within the function definition to have the function return a value to the handler that called it. If you don't use return, the function evaluates to empty.