Transposition: Switching the symbols within the plaintext Substitution: Substituting different symbols for the symbols in the plaintext
1. Transposition Cipher (Reversal Method)
The letters are rearranged but remain the same. This simple reversal method reads the message backwards.
Example: "HELLO" → "OLLEH"
Notice: Same letters (H,E,L,L,O), just rearranged
Ciphertext:
2. Transposition Cipher (Rail Fence Method)
Letters are written in a zigzag pattern across multiple "rails" and then read off row by row.
Example with 3 rails: "HELLO WORLD"
Rail 1: H . . . O . . . R . . → H O R
Rail 2: . E . L . W . L . D → E L W L D
Rail 3: . . L . . . O . . . → L O
Result: "HORELWLDLO"
Ciphertext:
3. Substitution Cipher (Caesar Cipher)
Each letter is replaced with another letter by shifting it a fixed number of positions in the alphabet.
Example with shift of 3:
A→D, B→E, C→F, D→G, E→H, F→I...
"HELLO" → "KHOOR"
Notice: Different letters, but pattern remains (H becomes K, E becomes H, etc.)
Ciphertext:
4. Substitution Cipher (Custom Alphabet)
Each letter is replaced with a completely different letter using a substitution alphabet.