Yes, the cosmetics (form) of serve differ from player to player, but most top serves share a range of common technical 'points' or 'moments' throughout the action (function).
Let's look at the preparation phase (set up > backswing and ball placement > pre-throw position) demonstrated here by Beth Grey.
- Relaxed continental grip
- Semi-closed stance - front foot towards net post, back foot parallel to baseline
- 'Palm-in' racket 'side-on
Backswing and ball placement (toss)
- Both arms down together before separating
- Ball placement arm goes up earlier than racket arm
- Ball is released at eye level
- Knees bend as ball goes 'up'
- Foot up (if) after ball toss and before load position
Pre-throw position (often a moment in time with racket arm moving rather than a still/fixed position)
- Elbow is stable at 90 degrees (elbow to trunk)
- Elbow is stable at 90 degrees (elbow to hand)
- Pre- throw position when ball is at the apex
- Slight tilt from front shoulder, back shoulder and back elbow
- Palm of hand facing side fencing (palm out)
- Both hips facing side fencing
- Knees at most flexed in pre-throw position
- Hip dipped slightly into the court
- Eyes and head are focused on impact area