Final answer:
Encryption is the process used to convert plaintext into ciphertext by manipulating the original text using a specific algorithm or method. The Transposition Cipher is a common encryption technique that involves rearranging the letters in the plaintext based on a predetermined keyword.
Step-by-step explanation:
The process used to convert plaintext into ciphertext is called encryption. Encryption is a method of encoding information so that it cannot be understood without the corresponding decryption key. The underlying logic of this process is to manipulate the original text using a specific algorithm or method to create ciphertext that appears random and unintelligible to anyone without the decryption key.
A common encryption technique is the Transposition Cipher, which involves rearranging the letters in the plaintext according to a specific rule or pattern. For example, the plaintext can be divided into blocks and the letters within each block can be rearranged based on a predetermined keyword. This keyword determines the size of the blocks and the specific change made to the order of the letters.