What are some good online/free resources (tutorials, guides, exercises, and the like) for learning Lambda Calculus?
Specifically, I am interested in the following areas:
- Untyped lambda calculus
- Simply-typed lambda calculus
- Other typed lambda calculi
- Church's Theory of Types (I'm not sure where this fits in).
(As I understand, this should provide a solid basis for the understanding of type theory.)
Any advice and suggestions would be appreciated.