Why are S / H used for Debit / Credit indicators?

I am new to SAP and am curious as to what the S and H indicators actually stand for, probably in German? Being American, I am accustomed to D=Debit, C=Credit, which is easy to remember. If I could associate a word with each of the letters S and H, it would make it easier for me to remember which is which. Even if the words were German, that would be very helpful.

Thank you,