Peerage of England
The ranks of the English peerage are, in descending order, Duke, Marquess, Earl, Viscount, and Baron. While most newer English peerages descend only in the male line, many of the older ones (particularly older baronies) can descend through females. Under English inheritance law all daughters are co-heirs, so many older English peerage titles have fallen into abeyance between various female co-heirs.
Barons in Scotland
An English barony is a peerage (yet the abolition act of 1660 allows for some remaining non-peer baronies not converted by writ to remain as feudal baronies of free socage "incorporeal hereditament" similar to a lordship of the manor), but whether Scottish barons rightfully rank as peers is disputable. They are known as minor barons currently treated as noble titles of less than peerage rank. The Scottish equivalent of an English baron is "Lord of Parliament".