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+# Monoalphabetic substitution - HTML/JS
+
+Tiny tool to do monoalphabetic substitution. Text can be added to the plaintext
+area or the encrypted text area. Substitutions are then added in the designated
+fields. The text can be decrypted or encrypted by a press on the buttons.
+**WARNING: Encryption en decryption override the textarea on the other side.**
+
+To accommodate easy trial and error the text being encrypted/decrypted will
+always be in lower case. The (currently) unedited output will appear as a
+capital, while the substituted characters will appear in lower case as well.