This section is from the book "Elementary Banking", by John Franklin Ebersole. Also available from Amazon: Elementary Banking.
The holder of an instrument has a right to payment in full when a note becomes due. But he may, if he wishes, let the maker pay in installments when he cannot pay the full amount. Care must be taken in such cases to compute exactly the amount due in principal and interest at every payment. Partial payments should be indorsed on the instrument in some such form as "Received on the within note $50 January 6, 1922. (Signed) Henry J. Peters."
To indorse a note, which enables some other person to collect on it, the payee writes his name across the back of it. This makes the payee, like the maker, responsible for the payment of the note. The person to whom he has indorsed it may indorse it to some other person (unless the first indorsement was a restrictive indorsement). All those who indorse a note are liable for the payment of it, except when the indorsement is qualified. Notes which have only one person responsible for their payment are called "single-name paper"; those having two or more responsible signers are called "double-name" or "three-name" paper. When the maker draws a note payable to himself, it is not complete until he has indorsed it. The rules regarding indorsement of notes are the same as for drafts, as previously explained.