Lecture Notes
- Notes for a class at Virginia Tech covering formal languages and their connections with finite automata, pushdown automata and Turing machines.
- http://courses.cs.vt.edu/~cs4114/lectures/index.html

Grammars
- A set of slides on grammars and language generation, with examples including a grammar for an abbreviated C language.
- http://www.cs.princeton.edu/courses/archive/fall2000/cs126/lectures/T3-4up.pdf#search=%22context%20sensitive%20languages%20compilers%22

Grammars And Parsing
- An article with examples from natural languages, parsing with YACC, the use of LL(k) grammars and the hierarchy of regular, LL(k), LR(k), context free, context sensitive and unrestricted grammars.
- http://www.cs.usfca.edu/~parrt/course/652/lectures-Spring-2004/formal.language.html

The Chomsky Hierarchy of Formal Grammars
- A brief definition of the grammars which define the Chomsky hierarchy of families of languages.
- http://www.spectrum.uni-bielefeld.de/Classes/Winter97/IntroCompPhon/compphon/node66.html

A Hierarchy of Languages
- A brief discussion of context sensitive languages, recursively enumerable languages and languages with no grammars. Examples show these are not equivalent.
- http://web.cecs.pdx.edu/~jhein/lectures/Section.14.2.pdf#search=%22context%20sensitive%20languages%22

Formal Language Theory
- An introductory approach to the topic using many examples.
- http://everything2.com/index.pl?node_id=113762

Formal Language Theory and Parsing
- This site includes chapters on regular and context-free languages as well as bottom-up and top-down parsing using LR(k) parsers.
- http://www.cs.nuim.ie/~jpower/Courses/parsing/