It represents something. For example, the symbol of a cross will convey a world of meaning to a Christian. The peace symbol and the acronym VC will mean certain things to a Vietnam veteran. The acronym IRS means headache for most of us. The blindfolded woman holding a scales, the Eiffel Tower, Big Ben, the Statue of Liberty - all convey information.
Some symbols have inherent meaning.
They are universal, part of the collective psyche of our culture, and will convey information just as they are. They may possibly even represent things we can t describe, enabling us to think more productively about the nature of the cosmos. Other symbols are created. These are called iconic symbols, and have to be loaded. For example, short-term forgetfulness might be symbolized by leaving eye glasses in unusual places.