Now, let's find out how our initial two patchcords (pitch and velocity) in the MIDI part of our synth became one. Of course, they were packed into a list by an object that's conveniently called [pack]. Lists are great. However, there are not only lists that consist of two integers; for example, there is the [coll] object that manages larger amounts of data, but also dictionaries in Max 6. Look at the list_examples.maxpat patchers, which are also depicted in the following screenshot, to get into lists a bit, and datatypes.maxpat (which is not depicted here) to get a feeling of datatypes and the conversion between them:

We will meet lists often and get more and more familiar with them. The key objects are [pack]/[unpack], [pak], [join]/[unjoin], [vexpr], [zl], [append]/[prepend], [route], [table], [itable], [coll], and the [dict] family. To look at a more concrete and usable example of some list-related techniques, let's look at the midi_abbr_configure.maxpat patcher:

This...