Unit 1 Unit 1 An overview of Computer System Classification of Computers

Supercomputer Mainframe computer Minicomputer Desktop computer –Microcomputer –Home computer –Personal computer –Workstation –Server –Special communications computer

Portable computer (or luggable computer) Wearable computer Embedded computer Mobile Computers –Desktop Replacement Computer –Laptop Computer –Tablet Personal Computer –Handheld Computers Pocket Computer Calculator Classification of Computers

Personal or micro Mini Main Frame Super Classification of Computers

Personal = micro Portable Types: Hand-heldPalmtop Notebook Classification of Computers

Personal = micro Portable Types: Hand-heldPalmtop Notebook Desktop Classification of Computers

Personal = micro Portable Types: Hand-heldPalmtop Notebook Workstations Desktop Users: anyone requiring modest computing facilities Classification of Computers

What is a notebook computer? –Portable, small enough to fit on your lap –Also called a laptop –Generally more expensive than a desktop computer

Handheld Computers What is a personal digital assistant (PDA)? –Provides personal organizer functions Calendar Appointment book Address book Calculator Notepad

Minicomputers Originally for specific tasks, like engineering calculations Users: medium-sized organisations or departments of large companies. Classification of Computers

Servers (how it’s used more than what it is) Designed to support a computer network More powerful Larger memory Larger storage capacity High speed communications

What types of servers are there? Midrange server- Powerful, large computer that supports up to a few thousand computers Mainframe- Very powerful, expensive computer that supports thousands of computers Supercomputer- The fastest, most powerful, most expensive computer. Used for applications requiring complex mathematical calculations

Main frame Large systems for hundreds of users Requires special environment IBM the main manufacturer (AS/400) –More common in large organisations Users: insurance companies, banks, airlines Classification of Computers

Supercomputers Extremely powerful machines for applications requiring extreme accuracy (e.g. NASA, earth sciences etc.) Used for weather forecasting, engineering design and testing, serious decryption Cost several million dollars Users: NASA, Meteorological Office. Classification of Computers