What is a thread ?

A thread is a number of events (or states) that must occur one after the other to perform a certain task.
Any event in the thread may cause the thread to suspend if the event cannot be completed.
The multi-threader shell will then re-activate the thread when the event is ready to complete.
A thread will be suspended if it is attempting to give data to a thread that is currently busy.

Here is a simple thread as an example -

1. Wait for a request to read the keyboard
   
2. Read the keyboard and wait for the RETURN key
   
3. Wait for the next thread to become idle
   
4. Pass data into the next thread
   
5. Go back and do event 1 again