What is +?

The symbol "+" is commonly known as the plus sign or addition sign. It is used to indicate the operation of addition in mathematics, typically between two or more numbers. The symbol originated from the Latin word "et" meaning "and," as it was used to add together values. It is also commonly used in computer programming languages to denote addition or concatenation. Additionally, the plus sign is commonly used as a symbol of positivity and to indicate more of something, such as a "+" sign on a battery indicating a higher charge level.