A stock certificate is a physical document that represents ownership of a specific number of shares in a company. It serves as proof that the holder is a shareholder and has a claim on the company's assets and earnings. Stock certificates typically include details such as the company's name, the shareholder's name, the number of shares owned, and a unique identification number. In the past, stock certificates were commonly issued in paper form, but many companies now use electronic records instead. This shift to digital formats has made it easier to manage and transfer ownership of shares, reducing the need for physical documents in the world of investing.