hi

here is BNF grammer.Can anybody help me to understand it.

<bool exp> -> <bool term> { "&" <bool term>}

<bool exp> -> "!" "(" <bool exp> ")"

<bool exp> -> <relation> { "|" <relation>}

<relation> -> <exp> ("=" | "<" | ">") <exp>

<exp> -> <term> {"+" <term> | "-" <term>}

<term> -> <factor> { "*" <factor> | "/" <factor>}

<factor> -> <number> | "(" <exp> ")"

here.inside double quote marks are terminals symbols,but | alone is a meta-symbol in the grammer.