Which of these forms of communication is text-based?

Electronic mail, commonly shortened to “email,” is a communication method that uses electronic devices to deliver text-based messages across computer networks. "Email" refers to both the delivery system and individual messages that are sent and received. Modern forms of email became available for widespread public use with the development of email client software and web browsers. Today, email is one of the most popular methods of digital communication. Its prevalence and security vulnerabilities also make it an appealing vehicle for cyber attacks like phishing, domain spoofing, and business email compromise (BEC).

Source: Cloudflare