Overview –

1. Thumb
2. Index finger
3. Middle finger
4. Ring finger
5. Little finger

Nomenclature of hand muscles –

1. Pollicis – for thumb.

Example:
Opponens Pollicis (OP)
Abductor Pollicis Longus (APL)
Extensor Pollicis Brevis (EPB)
Extensor Pollicis Longus (EPL)

2. Digitorum – for index, ring, middle and ring finger.

Example:
Flexor Digitorum Superficialis (FDS)
Flexor Digitorum Profundus (FDP)
Extensor Digitorum (ED)

3. Digiti minimi – for little finger.

Example:
Abductor Digiti Minimi (ADM)
Flexor Digiti Minimi (FDM)
Opponens Digiti Minimi (ODM)

4. Indicis – for index finger. 

eg. Extensor Indicis (EI)