Cryptography

English has three words for el relleno and uses a different one in every room. Here it is padding: el relleno criptográfico, the bytes added so that the last block comes out whole. In a kitchen it is stuffing — pimientos rellenos, el relleno del pavo. In a piece of writing or a speech it is filler, the part that says nothing. And rellenar is what one does to a form: rellene el formulario. One verb for filling anything at all, and four English words waiting on the other side.