&& && ... is the logical AND function. It evaluates its arguments in order, giving False immediately if any of them are False, and True if they are all True.
And[, , ... ] can be input in StandardForm and InputForm as ... . The character can be entered as &&, and or \[And].
And evaluates its arguments in a non-standard way (see Section A.4.2).
And gives symbolic results when necessary, removing initial arguments that are True.
See The Mathematica Book: Section 1.5.6.
See also: LogicalExpand, BitAnd, Nand.