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CS 101 Introduction to Computing Lecture 4 Computer Systems CS 101 Introduction to Computing Lecture 4 Computer Systems

During the Second Lecture … • We talked about the evolution of computers • During the Second Lecture … • We talked about the evolution of computers • How initial computers were mechanical, and then came electro-mechanicals, then tubebased, and finally transistor based, and how the future belongs to quantum computers • We discussed how the size is drastically decreasing with time and how their capability is increasing year by year

Today’s Goal 1. To learn to classify computers according to their capability and targeted Today’s Goal 1. To learn to classify computers according to their capability and targeted applications 2. To find out about the essential building blocks that make up a modern computer

Computer Types According to Capability • Supercomputers • Mainframes • Servers • Desktops • Computer Types According to Capability • Supercomputers • Mainframes • Servers • Desktops • Portables

Supercomputers (1) • State-of-the-art machines designed to perform calculations as fast as the current Supercomputers (1) • State-of-the-art machines designed to perform calculations as fast as the current technology allows • Used to solve extremely complex and large-scale problems: weather prediction, simulation of atomic explosions; aircraft design; movie animation • Cost tens of millions of dollars • Unique in that unlike mainframes & personal computers, designed to focus all their resources and capabilities on a single task at a time

Supercomputers (2) • Early supercomputers used a single or a few processors working in Supercomputers (2) • Early supercomputers used a single or a few processors working in parallel • Those processors were custom-built for the supercomputers, and were, therefore, very expensive • Modern supercomputers use the same processors that are used in desktop PCs. They, however, are designed to use 1000’s of them working together in parallel

Why use many not-sopowerful processors working in parallel ? Why not just design a Why use many not-sopowerful processors working in parallel ? Why not just design a single, really powerful processor ? Post your answers on the CS 101 message board

The Champion: ASCI White • Most powerful computer as of February 2002 • Capable The Champion: ASCI White • Most powerful computer as of February 2002 • Capable of 12. 3 trillion calculations/sec – 74, 000 times faster than Cray 1 (1976) – 1, 000 times faster than Deep Blue (1997) • Designed for complex 3 -D simulations required for testing nuclear weapons • Powered by 8192 microprocessors • 6 TB of memory; 160 TB of storage capacity

Mainframe Computers (1) • Also called “Enterprise Servers” • Designed for performing multiple, intensive Mainframe Computers (1) • Also called “Enterprise Servers” • Designed for performing multiple, intensive tasks for multiple users simultaneously • Used by large businesses (e. g. banks, ecommerce sites), military, and industrial organizations

Mainframe Computers (2) • Designed for very-high reliability • Can be serviced/upgraded while in Mainframe Computers (2) • Designed for very-high reliability • Can be serviced/upgraded while in operation • Generally consist of multiple processors, GB’s of memory, and TB’s of storage • Cost in millions of dollars

Servers/Minicomputers (1) • The name minicomputers used to define the class of computers that Servers/Minicomputers (1) • The name minicomputers used to define the class of computers that lies between personal computers and mainframes • Then very high-end desktop computers – called low-end or mid-range servers – took over the role that was previously played by minicomputers

Servers/Minicomputers (2) • Low-end and mid-range servers are used by small businesses and organizations Servers/Minicomputers (2) • Low-end and mid-range servers are used by small businesses and organizations as filestores, to run e-mail systems and Web sites • Generally are more reliable than desktops, but not as solid as the mainframes • Generally consist of 2 or more processors, GB’s of memory, and TB’s of storage • Costs in hundreds of thousands of dollars

Desktop Computers (1) • Also called microcomputers • Low-end desktops are called PC’s and Desktop Computers (1) • Also called microcomputers • Low-end desktops are called PC’s and high-end ones “Workstations” • Generally consist of a single processor only, some times 2, along with MB’s of memory, and GB’s of storage

Desktop Computers (2) • PC’s are used for running productivity applications, Web surfing, messaging Desktop Computers (2) • PC’s are used for running productivity applications, Web surfing, messaging • Workstations for more demanding tasks like low -end 3 -D simulations and other engineering & scientific apps • Are not as reliable and fault-tolerant as servers • Workstations cost a few thousand dollars; PC around a $1000

Mobile Computers (1) • Laptops, palmtops, and wearable computers are very capable computers but Mobile Computers (1) • Laptops, palmtops, and wearable computers are very capable computers but are light-weight and consume very little power • Laptops (also called notebook computers) generally weigh around 2 kg, use special low-power processors, typically have 256 MB memory, 40 GB of storage, can work for more than 2 hours on battery • Their usage is similar to that of PCs • They cost in the range of $1500 -2500

Mobile Computers (2) • Palmtops, also known as PDA’s - Personal Digital Assistants • Mobile Computers (2) • Palmtops, also known as PDA’s - Personal Digital Assistants • Weigh less than a pound, have very low-power processors, KB’s of memory, MB’s of storage capacity • Can run for many hours on AA batteries • Used as an electronic version of a pocket diary. Also for Web surfing and e-mail or even as mobile phones • Palmtops cost $200 -600

Mobile Computers (3) • Wearables are small in size, carried in a pocket, worn Mobile Computers (3) • Wearables are small in size, carried in a pocket, worn on the arm, waist, or head or elsewhere on the body • Capability similar to PDA’s, but more expensive • They are always ON, and always accessible. That is, the user can always enter and execute commands, even while walking around or doing other activities • Each soldier of the future will be fitted with one

Click here to view the picture of a wearable computer Click here to view the picture of a wearable computer

Ranking w. r. t. installed number • • PC’s PDA’s Workstations Servers Wearables (will Ranking w. r. t. installed number • • PC’s PDA’s Workstations Servers Wearables (will take the top spot in future) Mainframes Supercomputers

Now that we have learnt about the various types of computers and about their Now that we have learnt about the various types of computers and about their typical applications, let’s move on to a new topic Let’s now find out about the essential components that are present in every type of computers

At the highest level, two things are required for computing Hardware: The physical equipment At the highest level, two things are required for computing Hardware: The physical equipment in a computing environment such as the computer and its peripheral devices (printers, speakers, etc. ) Software: The set of instructions that operates various parts of the hardware. Also termed as “computer program”

We’ll have a lot to say about software during the duration of this course We’ll have a lot to say about software during the duration of this course However, for the rest of today’s discussion, let’s concentrate on hardware

All computers have the following essential hardware components: Input – the component through which All computers have the following essential hardware components: Input – the component through which a user instructs a computer about what to do Processor – the engine that processes the instructions given by the user Memory – where the processor stores information that is required during its computations Storage – where information that is required to be used much later is stored Output – the component that communicates the results of a computation to the user

There is another quite essential component that is present in every computer … ? There is another quite essential component that is present in every computer … ? ?

The Bus! The Bus!

Control Integer Unit Keyboard Mouse Compact Disk Floating Cache Point Memory Unit Processor System Control Integer Unit Keyboard Mouse Compact Disk Floating Cache Point Memory Unit Processor System Bus Memory Printer Monitor Hard Disk

Input Devices • • • Mouse Keyboard Joystick Camera Microphone Scanner Input Devices • • • Mouse Keyboard Joystick Camera Microphone Scanner

What’s a Port? What’s a Port?

Port The connection point at which we connect input and output devices to a Port The connection point at which we connect input and output devices to a computer

Many Types of Ports 1. 2. 3. 4. 5. Parallel Serial SCSI USB Firewire Many Types of Ports 1. 2. 3. 4. 5. Parallel Serial SCSI USB Firewire

Processor • • Pentium Celeron Athlon Power. PC Strong. ARM (PDA) Crusoe (Laptops) SPARC Processor • • Pentium Celeron Athlon Power. PC Strong. ARM (PDA) Crusoe (Laptops) SPARC (Workstations)

Memory/Storage • • RAM Punch cards ROM Hard disk Floppy disk Tape CD DVD Memory/Storage • • RAM Punch cards ROM Hard disk Floppy disk Tape CD DVD

Classifying Memory/Storage • Electronic (RAM, ROM) magnetic (HD, FD, Tape), optical (CD, DVD) • Classifying Memory/Storage • Electronic (RAM, ROM) magnetic (HD, FD, Tape), optical (CD, DVD) • Volatile (RAM), non-volatile (HD) • Direct access (RAM, HD), serial access (Tape) • Read/write (HD, RAM), read-only (CD)

Output Devices Printer Plotter Speakers Monitor Output Devices Printer Plotter Speakers Monitor

modem input device or output device? modem input device or output device?

mo dem mo dem

modem modulator demodulator mo dem modem modulator demodulator mo dem

Modem is an example of a device that acts both as an input as Modem is an example of a device that acts both as an input as well as an output device • Can you think of any other such dualpurpose devices? – Network cared – Touch screens

What have we learnt today? What are the various types of computers with respect What have we learnt today? What are the various types of computers with respect to their size, capability, applications (FIVE TYPES) The five essential components of any computer are input devices, processor, memory, storage and output devices

Next time we’ll find out about 1. What are the major building blocks of Next time we’ll find out about 1. What are the major building blocks of a modern personal computer? 2. How those building blocks are put together to form a PC?