What is flash memory

Flash memory :

It  is an electronic (solid-state) non-volatile computer storage medium that can be electrically erased and reprogrammed.

Toshiba developed flash memory from EEPROM (electrically erasable programmable read-only memory) in the early 1980s and introduced it to the market in 1984. The two main types of flash memory are named after the NAND and NOR logic gates. The individual flash memory cells exhibit internal characteristics similar to those of the corresponding gates.

Whereas EPROMs had to be completely erased before being rewritten, NAND-type flash memory may be written and read in blocks (or pages) which are generally much smaller than the entire device. NOR-type flash allows a single machine word (byte) to be written—​​to an erased location—​​or read independently.

The NAND type operates primarily in memory cards, USB flash drives, solid-state drives (those produced in 2009 or later), and similar products, for general storage and transfer of data. NAND or NOR flash memory is also often used to store configuration data in numerous digital products, a task previously made possible by EEPROM or battery-powered static RAM. One key disadvantage of flash memory is that it can only endure a relatively small number of write cycles in a specific block.^[1]

Example applications of both types of flash memory include personal computers, PDAs, digital audio players, digital cameras, mobile phones, synthesizers, video games, scientific instrumentation, industrial robotics, and medical electronics. In addition to being non-volatile, flash memory offers fast read access times, although not as fast as static RAM or ROM.^[2] Its mechanical shock resistance helps explain its popularity over hard disks in portable devices, as does its high durability, ability to withstand high pressure, temperature and immersion in water, etc.^[3]

Although flash memory is technically a type of EEPROM, the term "EEPROM" is generally used to refer specifically to non-flash EEPROM which is erasable in small blocks, typically bytes.^{[citation needed]} Because erase cycles are slow, the large block sizes used in flash memory erasing give it a significant speed advantage over non-flash EEPROM when writing large amounts of data. As of 2013,^{[needs update?]} flash memory costs much less than byte-programmable EEPROM and had become the dominant memory type wherever a system required a significant amount of non-volatile solid-state storage.

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What is computing?

The process of utilizing computer technology to complete a task. Computing may involve computer hardware and/or software, but must involve some form of a computer system. Most individuals use some form of computing every day whether they realize it or not. Swiping a debit card, sending an email, or using a cell phone can all be considered forms of computing. "Mason understood that his new job at the large IT firm would require a large portion of computing projects."

The computer memory:

It is a temporary storage area. It holds the data and instructions that the Central Processing Unit (CPU) needs. Before a program can be run, the program is loaded from some storage medium into the memory. This allows the CPU direct access to the program. Memory is a need for any computer.

A computer is usually an electrical device, which understands only electricity on and electricity off. This is expressed by using two symbols – 0 and 1 – which are called binarydigits or bits. Numbers and text characters are represented as codes, which are made up of combinations of 0s and 1s. Simple character codes are called ASCII (the American Standard Code for Information Interchange), and Unicode. In ASCII, eight bits – any combination of 0s and 1s – form one character or symbol. For example, the letter A is denoted by the code 01000001. The basic working unit of the computer's memory is a group of eight bits, which is called a byte.

The computer's memory consists of many millions of bytes. To make it easier, the unit K (for kilobytes) can be used to express memory capacity. One K equals 1,024. For example, 64K bytes of memory is the same as 65,536 (1,024 × 64 = 65,536) bytes. For larger memory capacities, the units mega and giga can be used. One megabyte of computer memory usually means 1024 kilobytes, which is 1,048,576 bytes, whereas one gigabyte means 1024 megabytes, which is 1,073,741,824 bytes. The size of the memory address that the computer uses limits the number of bytes it can handle.

The CPU calls instructions and data from the computer's memory. Because the same computer performs different tasks at different times, the memory is erasable—much like an audio cassette. Part of the memory, However cannot be erased.

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