SSD and HDD both have similar functions but store data differently.
HDD or hard disk drive is much cheaper then a SSD but offers more storage capacity, going a high as 10TB they use more energy as compared to the SSD and is less durable due to its mechanical parts.
SSD or the solid state drive does not offer much storage capacity then the HDD and can go as high as 4TB it also uses flash memory to deliver superior performance and durability.Without moving parts, SSD’s are more durable, run cooler and use less energy,SSDs are newer technology, and as such, are more expensive than HDDs. Although they are catching up, it can be harder to find large-capacity solid state drives. HDDs can be as much as 2.5 times larger.There are several connector types that SSDs use to interface with a computer, including SATA, PCIe, M. 2, U. 2, mSATA, SATA Express.