cs 11 7.7

An expression in Python is any valid combination of operators , literals and variables. In python there can be the following types of expressions: Arithmetic : a+b Relational : a>b Logical : a or b String : ‘a’*2 Compound : a+b>c**d

An atom is something that has a value. Identifiers, Literals, Strings, Lists, Tuples, Sets, Dictionaries etc. are all atoms.