Although a lot of information is covered in lectures, tutorials, and example patchers, I thought it would help to put together some explanatory posts that cover some basic concepts of MaxMSP and computing. This post explains objects and messages.
Everything in Max, everything you see, is an object. Integer number boxes, floating-point number boxes, message boxes, comment boxes, sliders, dials, toggles, buttons, and things such as makenote that have the object name and arguments are all objects. Objects do things.
The makenote object takes a note number, velocity, and duration and creates noteon and corresponding noteoff messages. An integer number box receives an incoming number, displays it, and then outputs the number. A button sends a bang message. And so on.
Notice that I include message and comment boxes as objects. A comment is an object that allows you to display typed text and numbers in your patcher. A message box allows you to output a pre-typed message when it receives any message, or when you click on it.
Any information that passes through a patch cord, or from one object to another object, is a message. Again, like there are different types of MaxMSP objects, there are different types of messages. Integer numbers, floating-point numbers, symbols (text), and bangs are all types of messages.
Since computers store information in different ways depending on the type of information, most computer programming languages differentiate between message types. An integer is different from a floating-point number. A symbol is different from any number. Some objects will complain (post error messages to the Max window) when they receive messages of the wrong type. Each object’s reference page lists the message types an object understands, by inlet.