by value

When calling a new function or procedure, all arguments need to be input to the function will be computed or copy to the new frame of this function, even it's an array or some more complicated data structure, the data will be fully copied to this function. Also after finishing calling this function, this frame disappears.

by reference

When calling a new function, each actual parameter is a pointer.

by copy-return

Similar to pass by value, except after the whole function, need to pass the modified value back to the outer frame

by name

When you need, you evaluate it and return the updated value back every time

by

Evaluate for the first time you need it and do not need to put the value back.