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   Flash memory refers to a particular type of electronically erasable programmable read-only memory (EEPROM). It is a computer memory chip that maintains stored information without requiring a power source. It is often used in portable electronics, such as digital music devices, smartphones and digital cameras, as well as in removable storage devices. This technology also is useful for computer basic input/output systems (BIOS), Personal Computer Memory Card International Association (PCMCIA) cards, modems and video game cards.

Speed Advantage

Flash memory differs from regular EEPROM in that EEPROM erases its content one byte at a time. This makes it slow to update. Flash memory can erase its data in entire blocks, making it a preferable technology for applications that require frequent updating of large amounts of data, as in the case of a memory stick for a digital electronic device.

Inside the flash chip, information is stored in cells. A floating-gate transistor protects the data that is written in each cell. Tunneling electrons pass through a low conductive material to change the electronic charge of the gate "in a flash," clearing the cell of its contents so that it can be rewritten. This is how flash memory gets its name.

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