1 Terms to learn

trackerball, n	шаровой указатель
joystick, n	джойстик
touch(-sensitive)screen, n	сенсорный экран
lightpen, n	световое перо
lever, n	рычаг, средство воздействия
graphics tablet, n	графический планшет
scanner, n	сканер
digital camera, n	цифровой фотоаппарат
microphone, n	микрофон
optical character recognition, n	оптическое распознавание знаков
solid state memory, n	твердотельная память
to download, v	загружать, скачивать
LCD(Liquid-Crystal Display), n	жидко-кристаллический (ЖК) экран
charge-coupled device, n	прибор с зарядовой связью, ПЗС
analog-to-digital converter, n	преобразователь из аналоговой формы в цифровую, цифратор
webpage, n	Web -страница, веб-страница, веб-документ, Интернет-страница
touchpad, n	сенсорная панель
binary, adj	двоичный (представленный в двоичной системе счисления)

2 Read the text

Input Devices

A variety of input devices can be connected to a computer to allow the user to input different kinds of data and to control the computer in different ways. Some common input devices and their functions are shown in the tables below.

Standard input devices

Device	Comments
keyboard	Main input device for controlling the computer and inputting text and numerical data
Cursor control input devices
Device	Comments
mouse	Common input device for use with a graphical user interface. The mouse sometimes has a ball underneath that is rolled on a mousemat.
trackerball	It is like a mouse turned upside down. The trackerball remains in one position while user rotates a small ball on top.
joystick	A vertical lever allows the user to control the cursor precisely and at high speed. Particularly good for playing fast action games.
touchscreen	The user interacts with a computer by lightly pressing their finger on a touch-sensitive area of the monitor screen.

Optical input devices

Device	Comments
Lightpen	It detects differences in reflected light. It can be used for drawing directly on the monitor screen or for reading printed optical characters or barcodes.
Graphical tablet	Used with a lightpen for drawing. The user draws on the tablet with a lightpen as if they were drawing on a sheet of paper.
Barcode reader	A special kind of lightpen for reading barcodes. Barcodes are used to identify items for stock control and pricing.
Scanner	Used to input text and graphics from a printed page.
Digital camera	Used to take pictures of an object. The picture is stored electronically and can be edited using a computer.
Voice input device
Device	Comments
Microphone	Used to input sound

Supplement

In electronics, a multi-level cell (MLC) is a memory element capable of storing more than a single bit of information. MLC NAND flash is a flash memory technology using multiple levels per cell to allow more bits to be stored as opposed to SLC NAND flash technologies, which uses a single level per cell. Currently, most MLC NAND stores four states per cell, so the four states yield two bits of information per cell. This reduces the amount of margin separating the states and results in the possibility of more errors. Multi-level cells which are designed for low error rates are sometimes called enterprise MLC (eMLC).

Flash memory stores data in individual memory cells, which are made of floating-gate transistors. Traditionally, one bit of data was stored in each cell in so-called single-level cells, or SLC flash memory. SLC memory has the advantage of faster write speeds, lower power consumption and higher cell endurance. However, because it stores less data per cell, it costs more per megabyte of storage to manufacture. Due to faster transfer speeds and longer life, SLC flash technology is used in high-performance memory cards.