One way I think Erlang was a kind of software emulating Tandem machine. - Joe Armstrong

When I'm writing a program, my approach is to "write a bit" and then "test a bit." I start with a small module with few functions, and then I compile it and test it with a few commands in the shell. Once I'm happy with it, I write a few more functions, compile them, test them, and so on. (page 60)

Comments are really good, so I would advise you to write comments. Write really big and expensive comments.

Our goal is actually to have about 75% utilization if we had one hundred CPU we would hope that our program will go 75% faster without tweaking it.