Commander (Royal Navy)
Commander (Cdr) is a senior officer rank of the Royal Navy of the United Kingdom.Before 1750, the rank was broadly considered as the limit of advancement for those without patronage, especially those who had been promoted from among a ship's crew.[4] By contrast, those with Parliamentary supporters or family connections were more likely to spend only a nominal period as master and commander of a sloop, before being elevated to post-captain.[3]: 130 Over the later 18th century, the rank evolved into a more regular stage of service between lieutenant and captain.Commanders unable to secure a ship were left ashore on half-pay, with limited prospects for future advancement.