Pocket watches were the first real mechanical watches. A pocket watch represented what most gentlemen adopted before the wristwatches, whose shape was that of a pocket watch with welded wire lugs and a leather strap, eventually hit the market. Back then, entrepreneurs, railway workers, doctors exclusively owned pocket watches, crafted in steel, silver, or precious metals. Ever since the first one originally appeared, a pocket watch used to be passed down as a family heirloom, from father to son.
As often showcased in vintage movies and as the name itself suggests, pocket watches were commonly placed inside a jacket or a waistcoat's small pocket. Pocket watches were, just like the wristwatch, available in multiple sizes, materials, and prices, thus covering a wide range of customers. For example, Breguet and Patek have created some of the most impressive and refined pocket watches, even though the first pocket watch dates back to much earlier.
As stated above, the origins of the pocket watch date back earlier than when the most refined and highly coveted hit the market. It was only after the invention of the spring-driven clock that the first mechanical pocket watches appeared, being the only watches available before the early 1900s. According to some sources of information, the pocket watch appeared in the 16th century. It was hard to talk about authentic pocket watches, in the beginning, since they were chunky and boxy. It was only in 1675 that men began to adopt pocket watches, thanks to Charles III of England's invention: the waistcoat. It was merely a matter of protecting these pieces, given that the first ones were all but sturdy and waterproof, like the current ones.