When you think of lighters, one of the most popular brands comes to mind. The Zippo Lighter! There are many fakes out there so identification is key. The Zippo lighter has a "date of manufacture" on the bottom that affects it's value. In the mid 50s these dates were stamped at the bottom of these windproof lighters. The date of manufacture is a valuable tool in identifying the style and model, and whether they are patented or patent-pending. The book Zippo Lighters: An Identification And Price, is a great coffee table book. It has a ton of pictures of old and new Zippo Lighters. There is also a price guide included in the book.