This document discusses Lexical Functional Grammar (LFG) and Generalized Phrase Structure Grammar (GPSG). LFG was developed in the 1970s and emphasizes analyzing phenomena in lexical and functional terms. It uses two levels of structure: c-structure, which is a tree structure, and f-structure, which captures grammatical functions. GPSG was developed in 1985 and is confined to context-free phrase structure rules. It uses immediate dominance and linear precedence rules.