The Greek alphabet is a writing system that has been used since the 8th century BCE. It consists of 24 letters, each representing a distinct sound. The alphabet is the basis for many modern scripts, including Latin and Cyrillic, and has played a significant role in the development of Western literature and science. The letters of the Greek alphabet include familiar characters such as Alpha, Beta, and Gamma. Each letter has an uppercase and lowercase form, and they are used in various fields, including mathematics and science, where Greek letters often symbolize specific constants or variables.