Haskell

What was the background to invention of monads?

Monads existed long before Haskell. Someone had the idea of using them in Haskell, but it was only later that the idea of using them for I/O was formed.

Nomadic pastoralism seems to have developed as a part of the secondary products revolution proposed by Andrew Sherratt, in which early pre-pottery Neolithic cultures that had used animals as live meat ("on the hoof") also began using animals for their secondary products, for example, milk and its associated dairy products, wool and other animal hair, hides and consequently leather, manure for fuel and fertilizer, and traction.

In the beginning, God created Simon Peyote Joints...

>>4
I think you mean Potato `Simon` Jones.

why is any program that uses the IO monad for more than just a single print at the end so slow?

>>5
Xarn detected.

Leibniz invented monads.
Seriously, if you want to learn Haskell, read his « La Monadologie ».

http://www.google.com/search?q="fictional+programming+language"