Computers (Hardware and Software)

Computer System A computer system consists of both hardware and information stored on hardware. Information stored on computer hardware is often called software. The hardware components of a computer system are the electronic and mechanical (physical) parts. The software components of a computer system are the data and the computer programs.

Perform four major functions Inside the Computer Understanding Your Computer Computers are Data-Processing Devices Perform four major functions Input: Gathers data, allows entering data Process: Manipulates, calculates, or organizes data Output: Displays data and information Storage: Saves data and information

Computers Inside the Computer Digital: The Language of Computers Analog – continuous waveforms Digital – data is described using only two states: on and off

Computers Inside the Computer Digital: The Language of Computers Digitize – to convert data, analog signals, and images into 1’s and 0’s used by computers

Computers Inside the Computer Digital: The Language of Computers Binary – two-digit numbering system 1 represents on 0 represents off Each 1 or 0 is called a bit Bit – short for binary digit

Computers Inside the Computer Digital: The Language of Computers Encoding systems ASCII – American Standard Code for Information Interchange ANSI – American National Standards Institute UNICODE – capable of handling most printed languages

Computers Inside the Computer Digital: The Language of Computers Byte – collection of bits that represent a character ASCII – 7 bits/byte ANSI – 8 bits/byte UNICODE – 16 bits/byte

Computers Inside the Computer Digital: The Language of Computers Binary (base 2) – numbers are represented only using 1’s and 0’s Hexadecimal (base 16) – used to represent numbers using fewer digits A=10, B=11, C=12, D=13, E=14, F=15 Decimal (base 10) = numbers are represented using 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9

Input Devices Enter data and instructions Examples Keyboard Mouse Microphone Scanner Digital camera

Output Devices Send data out of the computer in the form of: Text Pictures Sounds Video Examples Monitors Printers Speakers and earphones

Computers Inside the Computer The PC System Unit Connected to the Motherboard: Processor (CPU) Chipset Memory chips Expansion boards

Computers Inside the Computer The PC System Unit The Processor: Computer on a Chip Pentium 4 Celeron XeonTM ItaniumTM Intel Core processors Dominant processors (i7, i5, and i3)

Computers Inside the Computer The PC System Unit Central Processing Unit Control unit Arithmetic and logic unit

Computers Inside the Computer Central Processing Unit Control unit Reads and interprets instructions Directs the operation of internal processor components Controls the flow of programs and data in and out of RAM

Computers Inside the Computer Central Processing Unit Decoder – interprets instructions that have been retrieved from RAM Registers – high-speed working storage areas instruction register – contains instruction to be executed program register – contains location of next instruction to be executed

Computers Inside the Computer Central Processing Unit Arithmetic and Logic Unit Performs computations Performs logical operations (comparisons) Accumulator – register where answers are stored

Computers Inside the Computer RAM (Random Access Memory) High-speed holding area for data and programs Volatile memory – data is lost if electrical current is not maintained Address – specific location in RAM

RAM (Random Access Memory) Types Double data rate 3 (DDR3) Double data rate 5 (DDR5) Memory modules Dual inline memory modules (DIMMs) There are different types of RAM. In most systems, the type of RAM used is double data rate 3 (DDR3) memory modules, which is available in several speeds. The higher the speed, the better the performance. DDR5 memory, which has an even faster data transfer rate, is seen in high-performance video graphics cards. RAM appears in the system on memory modules, small circuit boards that hold RAM chips and fit into slots on the motherboard.

Computers Inside the Computer Cache Throughput – rate at which the computer works Cache Memory – CPU memory, is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. This memory is typically integrated directly with the CPU chip or placed on a separate chip that has a separate bus interconnect with the CPU - faster than RAM

Computers Inside the Computer Other High-Speed Memories ROM (read-only memory) – Start-up instructions stored here Permanent nonvolatile storage PROM (programmable ROM) – user can store read-only programs and data

Computers Inside the Computer Other High-Speed Memories Flash Memory Nonvolatile memory – does not lose data in a power outage Easily upgraded BIOS (Basic Input Output System) – stored in flash memory

Computers Inside the Computer The Instruction Set and the Instruction Cycle Machine language – what a computer actually understands All instructions to a computer must be converted to binary

Computers Inside the Computer The Instruction Set and the Instruction Cycle Instruction Sets CISC (complex instruction set computer) – understands many different instructions RISC (reduced instruction set computer) – understands a smaller list of instructions

Computers Inside the Computer The Instruction Set and the Instruction Cycle Instruction Cycle Instruction time (I-time) – instruction is retrieved from memory and decoded Execution time (E-time) – instruction is executed and result is placed in memory Decoding is the process of transforming information from a difficult to understand stored symbols format to one that is easier to understand -which is the reverse of encoding.

Computers Inside the Computer Buses and Ports PCI (peripheral component interconnect) local bus – allows for circuit boards to connect to the common system bus

Computers Inside the Computer Buses and Ports Expansion slots – where expansion boards are installed Expansion boards or expansion cards – provide additional capabilities to the computer

Computers Inside the Computer Buses and Ports USB (universal serial bus) – used to connect peripheral devices to the PC USB hub – connects to the USB port and provides additional places to plug USB devices

Computers Inside the Computer Legacy and Other PC Ports Serial port – data flows one bit at a time Parallel port – data flows several bits at a time IrDA port or infrared port – data sent by light waves

Computers Inside the Computer PC Growth: Adding Capabilities Expansion Boards – placed in expansion slots Graphics adapter Sound Data/voice/fax modem Network interface card (NIC) Small Computer System Interface card (SCSI) -(CD-ROM drives, CD recorders. Etc.) Video capture card

Computers Inside the Computer Build Your Own PC Advantages Cheaper (for high-end systems) Meets your requirements Disadvantages No warranty on system No help desk

Computers Inside the Computer Describing the Processor and Its Performance Core Speed: GHz, MIPS, and FLOPS Gigahertz (GHz) – billions of clock cycles per second Megahertz (MHz) – millions of clock cycles per second

Computers Inside the Computer Core Speed: GHz, MIPS, and FLOPS MIPS – millions of instructions per second FLOPS – floating point operations per second; used to measure speed of supercomputers

Computers Inside the Computer Bus Speed Most processors operate at GHz Most buses operate at MHz Major block to efficiency in a PC

Computers Inside the Computer Memory Capacity KB (kilobytes) – approximately 1000 bytes MB (megabyte) – approximately 1 million bytes GB (gigabyte) – approximately 1 billion bytes TB (terabyte) – approximately 1 trillion bytes

Computers Inside the Computer Memory Capacity Kb (kilobit) – approximately 1000 bits Mb (megabit) - approximately 1 million bits

Computers Inside the Computer Processor Design Parallel processing – multiple processors in one computer system Massively parallel processing (MPP) – parallel processing with thousands of processors

Computer Software Software: A set of instructions that tell the computer what to do Two basic types of software Application software System software Software refers to instructions that tell the computer what to do. An instruction set, also called a program, provides a means to interact with and use the computer. Your computer has two basic types of software. Application software is used to do tasks at home, school, and work. System software helps run the computer and coordinate instructions between application software and the computer’s hardware devices. System software includes the operating system and utility programs.

Understanding System Software What the Operating System Does? Operating System (OS) - Coordinates and directs the flow of data and information Operating system fundamentals Multitasking Networking capabilities Categorized by type You use application software to do everyday tasks at home and at work. System software helps run the computer and coordinates instructions between application software and the computer’s hardware devices. Modern operating systems allow a single user to multitask—to perform more than one process at a time. Operating systems such as Windows and OS X provide networking capabilities as well. Operating systems can be categorized by the type of device on which they’re installed.

What the Operating System Does The operating system is like an orchestra's conductor. It coordinates and directs the flow of data and information through the computer system. Copyright © 2016 Pearson Education, Inc.

Understanding System Software Operating Systems for Personal Computers Top three operating systems Windows Max OS X Linux Microsoft Windows, Mac OS X, and Linux are the top three operating systems for personal computers. The newest release of Microsoft’s OS, Windows 8, provides a new interface optimized for touch-screen devices. Now that broadband Internet access and providing computer resources via the Internet are becoming more commonplace, operating systems have features that are tied to cloud computing.

Multimedia software includes digital image- and video-editing software, digital audio software, and other specialty software required to produce computer games, animations, and movies.