The pound sign, represented by the symbol "#", is commonly used in various contexts. In the United States, it often denotes weight, specifically one pound, which is equivalent to 16 ounces. This symbol is also used in social media to create hashtags, allowing users to categorize and find content related to specific topics. In computing, the pound sign serves as a symbol for comments in programming languages like Python and Ruby. Additionally, it is used in telephony to indicate the end of a sequence, such as when entering a code on a phone keypad.