M.2 vs SSD vs HDD – Difference and Comparison

What is M.2?

M.2 is similar to a traditional hard drive-in terms of functionality but is much smaller in size used for storing data. M.2 drives are used in laptops and other portable devices where space is limited.

M.2 drives are available in different sizes. They can be used as a boot drive, meaning that the operating system and all of the installed programs are stored on the M.2 drive.

They can also be used as a data storage drive, where files and folders are stored just like on a traditional hard drive. M.2 drives are faster than traditional hard drives and use less power, which makes them ideal for laptops and other portable devices. They are also more resistant to shock and vibration, which further increases their reliability.

What is SSD?

Using integrated circuit assemblies as memory to store data persistently, solid-state drives (SSDs) are a type of data storage. new I/O interfaces like SATA Express and the PCI Express (PCIe) bus have been designed to address specific requirements of the SSD technology. SSDs have no moving (mechanical) components.

The majority of SSDs have NAND-based flash memory, which can store data without electricity. SSDs may be built from random-access memory for applications that require fast access but not necessarily data permanence after a power outage (RAM). Such devices may exhibit very fast data access, but data is not necessarily persisted after power loss.

What is HDD?

HDD stands for hard disk drive. It is a data storage device that uses one or more rigid, quickly rotating discs and platters coated in a magnetic material to store and retrieve digital information. Magnetic heads are linked with the platters, reading and writing data to the platter surfaces. These heads are positioned on a moving actuator arm.

Since data can be accessed at random, discrete blocks of data can be stored or retrieved in any order, rather than just sequentially. HDDs are a type of non-volatile storage, which means that the data is not lost when power is removed from the device.

HDDs are used in a variety of applications including desktop computers, laptops, servers, and storage arrays.

Difference Between M.2, SSD, and HDD

  1. M.2 drives are available in different form factors, while SSDs are only available in 2.5-inch form factors.
  2. M.2 drives can be used in a variety of different applications, while SSDs are used for data storage only.
  3. SSDs are a lot faster than HDDs; they can boot up your computer in a matter of seconds, whereas HDDs can take minutes.
  4. SSDs consume less power than HDDs, which can help your laptop‘s battery last longer.
  5. Hard disk drives connect to the motherboard via a SATA interface, while M.2 drives connect directly to the PCIe bus.
  6. Hard disk drives tend to be more affordable than M.2 drives, although the price gap is narrowing as M.2 technology becomes more popular.

Comparison Between M.2, SSD, and HDD

Parameters of comparisonM.2SSDHDD
Form factorSmaller than SSD and HDDSmaller than HDD, but higher transfer rateBigger than SSD but smaller than M.2
InterfaceUses PCI Express interfaceUses SATA interfaceUses SATA interface
CapacityLow capacityHigh CapacityHigh Capacity
PerformanceFast performance in comparison to SSD and HDDdoes not have any moving parts give resulting in a faster performancehas spinning disks as a result gives slow performance than M.2 and SSD
Reliabilityreliability is higher than SSD and HDDMore reliable than HDDreliability is lower because there are moving parts


  1. Flash SSD vs HDD: High performance oriented modern embedded and multimedia storage systems | IEEE Conference Publication | IEEE Xplore
  2. M2AP: A Minimalist Mutual-Authentication Protocol for Low-Cost RFID Tags | SpringerLink