Traditional hard disk drives (HDDs) are known as a legacy technology that has existed longer than SSDs. This data separation is called “disk fragmentation,” and most OSs have a built-in program that defragments the disk, rearranging the data so that information for a program is in one place. While the time is measured in milliseconds, more instances of data separation can cause a significant slowdown. The distance from the first sector to this new sector will add time to how quickly the data can be read.
When an update occurs to the data, the CPU will instruct the HDD to write it in the next available sector. When a CPU writes data onto the HDD, it uses a portion of a sector or sectors, depending on the size of the file. However, the tradeoff is the increased sensitivity to magnetic fields, which required more accurate read/write arms to be designed. This method stacks the sectors on their ends and creates more than three times the storage capacity of longitudinal recording. “Perpendicular recording” is a method created to combat issues found in longitudinal recording. At such a small scale, the bits would flip their charge randomly depending on temperature, causing data corruption. This horizontal alignment became a problem when increasing the HDD capacity by shrinking the sectors. The original design of hard drives included longitudinal recording that aligned the sectors horizontally to the drive’s spinning platter. Over the years of HDD development, there has been a change in sector layout on the platter. The bits of the sector and their corresponding charges are read by the read/write head and can be translated into binary as 1s or 0s. These sectors have thousands of subdivisions (called bits) that can all accept an electric charge. Each platter has an arm with magnetic heads, and each platter spins and is divided up into sectors.
This electrical charge comes from the actuator arm or “read/write head.” Read/write heads are instructed where to move on the platters by the software in the CPU and motherboard. How do hard disk drives (HDDs) work? Anatomy of an HDDĪn HDD has disc-like objects that are called “platters.” Platters are where the data is stored using an electrical charge. Today, by comparison, an HDD that fits easily in a desktop computer can have upwards of 18 terabytes worth of storage. HDDs started as massive, room-filling devices with a capacity of about 3.75 megabytes. The speed that the drive reads and writes this data is solely dependent on the drive itself. Operating systems (OS) tell the HDD to read and write data as needed by programs. An HDD is a “non-volatile” storage drive, which means it can retain the stored data even when no power is supplied to the device. If someone steals your laptop, they might take your hard drive, too, unless you store it elsewhere a flood or fire could destroy both your computer and hard drive if kept in the same place.What are HDDs and SDDs, and how are these types of storage similar and different? What is a hard disk drive (HDD)?Ī hard drive or hard disk drive (HDD) is a type of data storage device that is used in laptops and desktop computers.
Offsite protection. Cloud services – such as OneDrive, iCloud, Google Drive, and Dropbox – can protect your data from local threats, such as theft, fire, flood, nasty virus, power surge and hard drive failure. It’s recommended to have a couple of hard drives, in different locations, in case something happens to one of them.
Remember, you only need to buy the hard drive once, too. Paying as low as $50 for a brand-name 1TB external drive is less expensive than a cloud service over time (and once you stop paying, you’re without your files). Transferring files to a hard drive is also faster than uploading to the cloud.īang for the buck. SanDisk's ibi ($179) smart photo manager, for example, wirelessly backs up and organizes photos and videos stored on computers, smartphones and tablets (via an app), social media accounts, and cloud services, too. Easy data backup. While most cloud services offer an auto-backup feature, many hard drives today also have this feature.