Ciphertext is the result of applying an encryption algorithm to plaintext, which is the original readable data. This transformation makes the information unreadable to anyone who does not have the proper key or method to decrypt it. The purpose of ciphertext is to protect sensitive information from unauthorized access. When data is converted into ciphertext, it appears as a random string of characters, making it difficult to interpret without decryption. This process is essential in various fields, including cybersecurity, where protecting data integrity and confidentiality is crucial for individuals and organizations alike.