Hard drive storage device technology keeps changing – with improvements in data storage and reductions in size.

Not all that long ago IDE protocol was replaced by SATA for hard disk drives and this protocol was used for the early versions of solid state drives (SSDs).  Now we have the M.2 format but have you noticed that there are 2 different protocols for M.2 drives?

The SATA protocol was used for several years with SSDs

Note the 2 slots in the edge connector.

It plugs directly into the motherboard but operates at the exact same speed as a 2.5-inch SATA drive.

 

 

 

More recently and arguably the gold standard in drive technology is the NVMe protocol which has a big speed advantage by being directly connected to the PCIe bus.

Note the single slot on the edge connector.

It was released in various generations (Gen 3, Gen 4,
and Gen 5).