Storage

Hard Drive

The hard drive stores all your data. It controls the hard disk, where all your files and folders are physically located. A typical hard drive is only slightly larger than your hand, yet can hold over 100 GB of data. The data is stored on a stack of disks that are mounted inside a solid encasement. These disks spin extremely fast (typically at either 5400 or 7200 RPM) so that data can be accessed immediately from anywhere on the drive. The data is stored on the hard drive magnetically, so it stays on the drive even after the power supply is turned off.
The term "hard drive" is short for "hard disk drive." The "hard disk" refers to the actual disks inside the drive. However, all three of these terms are seen as refering to the same thing the place where your data is stored.

USB

The USB is technology that allows a person to connect an electronic device to a computer. It is a high-speed serial bus. It is most used on Personal computers. USB connects different devices using a standard interface. Most people use USB for computer mice, keyboards, scanners, printers, digital cameras, and USB flash drives.

Flash Cards

A flash card is a small data storage device that uses a flash memory chip to store data. Flash cards can be quite small in size, with a capacity of many gigabytes of storage. The memory in these cards is non-volatile, so it does not require a power source to remain intact. There are many different devices that use these cards for example computer, phones and gaming devices.

One of the major reasons that flash cards are highly reliable is because they have no moving parts, unlike a hard disk drive that spins while being used, creating more opportunities for malfunction. Flash memory can be accessed very quickly. Electrical charges erase this type of memory in "flashes," hence the name, "flash card." These cards are common in many devices, providing extra storage in products such as digital cameras, mobile phones, and video game devices.
Flash cards are very important in digital graphics as if it were not for flash cards you would not be able to store the data of your digital graphics and it would be lost.