Computer Systems and Apps

Registers

are small high-speed storage locations contained in the processor that temporarily hold data and instructions.

DIMMs

(Dual In-line Memory Module) is when the pins are on opposite sides of the circuit board and do not connect thus forming two sets of contacts.

Bits

8 bits per Byte. which transfer internally within the circuitry of the computer along electrical channels.

Multi-core processor

Multi-core processor is a single chip with two or more separate processor cores. Used in all sizes of computers.

Batteries

Not all batteries are removable, especially when referring to ultrathin laptops and some mobile devices. Batteries are generally rechargeable lithium-ion batteries.

Chassis

refers to the case on a desktop that contains and protects the motherboard, hard drive, memory and other electronic components.

Gigahertz

(GHz) equals one billion ticks per second. The faster the clock speed the more instructions executed per second by the processor.

ROM

(Read Only Memory) refers to memory chips storing permanent data and instructions. Read only means that the chip cannot be modified, is nonvolatile meaning their contents are not lost when power is removed from the computer. is included in peripheral devices like printers that may contain data for fonts on the ROM chips.

SIMMs

(Single Inline Memory Module) which has pins on opposite sides of the circuit board that connect together to form a single set of contacts.

Terabyte

(TB) Approximately 1 trillion bytes.

Addressable Memory

A byte known as a character, is the basic storage unit in memory. Instructions and data exist as bytes; each byte temporarily resides in a location in memory that has an address. An address is a unique number that identifies the location of a byte in memory. To access data or instructions, the computer reference the addresses that contain bytes of data.

Bytes

A byte known as a character, is the basic storage unit in memory. Instructions and data exist as bytes; each byte temporarily resides in a location in memory that has an address. An address is a unique number that identifies the location of a byte in memory. To access data or instructions, the computer reference the addresses that contain bytes of data.

Processor Cooling

A main fan is included in the main power supply of a computer to generate airflow, however, today's computers processors often require additional cooling. Heat sink is is a small ceramic or metal component with fans on its surface that absorbs and disperses heat produced by electrical components. Liquid cooling technology uses continuous flow of fluids like water or glycol to reduce the temperature of the processor by transferring the heated fluid away from the processor to a radiator-type grill which then cools the liquid and returns it cooled to the processor. Cooling pad is an item that you can purchase to place below your laptop to protect the computer from overheating. Some can include a small fan drawing power from a USB port.

The System Clock

A small quartz crystal circuit that controls the timing of all computer operations. Just as your heart beats regularly to keep your body functioning, the system clock generates regular electronic pulses, or ticks that set the operating pace of components of the system unit.

Memory Access Time

Access time is the amount of time it takes the processor to read data, instructions and information from memory. Access time directly affects how fast the computer processes data; accessing data in memory can be 200,000 time or more faster than accessing data on a hard disk. A variety of terminology is used today to state access times; some using fractions of a second.

Gigabyte

Bytes are what manufacturers use to state the size of memory available for storage. Gigabyte (GB) Approximately 1 billion bytes.

Cache

Cache is a temporary storage area. There are two common types of cache: Memory cache stores frequently used instructions and data.

CMOS

Complementary Metal-Oxide Semiconductor (CMOS) provides high speeds and consumes little power which is why some RAM chips and flash memory chips utilize it. CMOS uses battery power to retain information even when the power is off. Battery-backed CMOS memory chips can keep the calendar, date and time current even when the computer is off. Flash memory often uses CMOS technology to store a computer's start-up information.

The Arithmetic Logic Unit

Component of the processor Performs arithmetic, comparison and other operations. Includes basic calculations known as arithmetic operations: + - * / Comparison operations compares on data to another like > = < An example of comparison operations would be software calculating employee pay: regular vs. overtime

Clock Cycle

Each tick equates to a clock cycle. Processors are typically super scalar which means they can execute more than one instruction per clock cycle.

Chip

Integrated circuit can contain millions of elements: resistors, capacitors & transistors. A transistor acts as an electronic switch that opens or closes the circuit for electrical charges. Computer chips today include millions or billions of transistors. Chips are typically one-half inch square.

L1, L2, L3 Cache

Level 1 (L1) cache is built directly on the processor chip and has very small capacity Level 2 (L2) is slower than L1 but has much larger capacity. A type of L2 cache is the ATC (Advanced transfer cache) built directly on the processor chip. Level 3 (L3) cache is separate from the processor chip on the motherboard and exists only on computers that use L2 ATC.

Plug and Play

Plug and Play Technology refers to the computer's ability to automatically recognize peripheral devices as you install them. This means that you can begin using a device as soon as you plug it in. This technology permits computers to connect and communicate with devices easily but also creates security flaws that allow hackers to take control of things such as: security systems, routers, Smart TVs, printers, webcams and any other device connected to the Internet.

RAM

Random Access Memory, also called main memory, consists of memory chips that can be read from and written to. RAM can accommodate multiple programs and applications simultaneously. Saving is copying from RAM to a storage device.

Firmware

Rom chips called firmware contain permanently written data, instructions and information such as a computer's start up instructions.

Motherboard

Sometimes called a system board. This is the main circuit board of the computer. The processor, memory and other components attach to the motherboard.

Types of Buses

System bus also called the front side bus (FSB) is part of the motherboard connecting the processor to the main memory. The backside bus (BSB) connects the processor to the cache. The expansion bus allows the processor to communicate with peripheral devices. When the term bus is used by itself, it is usually referring to the system bus, front side bus (FSB).

Power Supply (AC/DC)

The AC adapter converts the AC power into the DC power that the peripheral requires. Or laptop adapter converts the wall outlet AC (Alternating Current) power into DC (Direct Current) power because the standard wall outlet supplies and unsuitable power.

USB

The USB adapter is a dongle that plugs into a USB port, enhances functions of a mobile computer, providing connections to peripheral devices.

Adapters

The USB adapter is a dongle that plugs into a USB port, enhances functions of a mobile computer, providing connections to peripheral devices. USB adapters can be used to add memory, communications, multimedia, security or storage.

Machine Cycle

The processor repeats a set of four basic operations for every instruction:

Control Unit

This is the component of the processor that directs and coordinates most of the operations in the computer. The control unit interprets each instruction issued by a program or an application and then initiates the appropriate action to carry out the instruction.

Adapter Cards - Identify types

Type Purpose Bluetooth Enables Bluetooth connectivity MIDI Connects to musical instruments Modem Connects to transmission media, such as cable television lines or phone lines Network Provides network connections, such as to an Ethernet port Sound Connects to speakers or a microphone TV tuner Allows viewing of digital television broadcasts on a monitor USB Connects to high-speed USB ports Video Provides enhanced graphics capabilities, such as accelerated processing or the ability to connect a second monitor Video Capture Connects to a video camera

Flash Memory

chips store data and programs on mobile devices and peripheral devices like smartphones and printers. Memory cards contain flash memory instead of on a chip for removable devices.

Memory

consists of electronic components that store instructions waiting to be executed by the processor, data needed by by those instructions and the results of processing the data. Memory consists of one or more chips on the motherboard or other circuit board.

Graphics/Video Card

converts computer output into a video signal traveling through a cable to the monitor to be displayed on the screen.

Bus Width

determines the amount of bits that the computer can transmit at one time. The larger the number the faster the computer transfers data. The wider the bus the fewer steps required and the faster data transfers.Most computers today use a 64-bit bus.

Non-Volatile Memory

does not lose its content when power is removed. It is permanent memory: ROM, flash memory, CMOS.

Sound Card

enhances the sound-generating capabilities of a personal computer; allowing sound to be input through a microphone and output through speakers or headphones.

Storing

in this context of machine cycle, storing is writing the result to memory (not to a storage medium).

Central Processing Unit

interprets and carries out basic instructions that operates a computer.

Heat Sink

is a small ceramic or metal component with fans on its surface that absorbs and disperses heat produced by electrical components.

Expansion Slot

is a socket on a desktop or server motherboard that can hold an adapter card.

Volatile Memory

loses its contents when power is removed. Memory is temporary, RAM.

Decoding

refers to the process of translating the instruction into signals the computer can execute.

Executing

the process of carrying out the commands.

Fetching

the process of obtaining a program or an application instruction or data item from memory.