What is the difference between an SSD and an NVMe M

SATA SSD vs PCIe SSD - What's the difference? nvme vs m 2 slot 2 is a form factor and therefore refers to the physical appearance, shape, and size of the drive, NVMe describes the interface of the SSD or, how the storage nvme m2 slot I want to add SSD drive in my notebook I find M2 slot marked as M2X3 What type M2 SSD can I use?

nvme m2 slot laptop 2 NVME SSDs with a notch is the strongest; from the compatibility, M 2