CFG Production rule


- (rule-)head results (rule-)body
- start symbol should have non-terminal or empty string
> $$nonterminal \,\,(head) \to  \{terminal\, |\,\, nonterminal \,\,|\,\, empty\} \,\,(body)$$
### - notational convention
![](https://www.notion.so/image/https%3A%2F%2Fs3-us-west-2.amazonaws.com%2Fsecure.notion-static.com%2F6fab06e4-4722-4314-a4b4-239883d99da4%2FUntitled.png?table=block&id=d62611e0-bac9-4a6a-8012-9372a7a78912&cache=v2)







