Samsung announced it will show off a prototype of what will become its first hybrid hard drive at the Windows Hardware Engineering Conference in Seattle next week.
Primarily designed for laptops, the drives will be less of a drain on batteries and will add an extra 20 to 30 minutes of battery life. The drive uses both NAND flash memory with the standard magnetic storage to allow users to boot up twice as fast.

According to Samsung the hybrid hard drives mean that the disks do not have to spin all the time because the NAND flash memory acts as a cache. It is also less likely to be damaged if it is dropped.

It seems they found a compromise between the two drives.

Source: The Inquirer