Laptops

A laptop is a portable personal computer with a clamshell form factor, suitable for mobile use. They are also sometimes called notebook computers or notebooks or lappy. Laptops are commonly used in a variety of settings, including work, education, and personal multimedia.

  • Similar in specification to a personal computer.
  • Monitor and keyboard are integrated into a single unit.
  • Can be used from the mains or with a built-in rechargeable battery.
  • More expensive than personal computers due to miniaturization of computer components.
  • Ideal computer for business people and ICT trainers who are constantly on the move.

What_is_the_best_laptop_2013_2014lap

 

 

Personal Digital Assistants/Handheld Computers

A personal digital assistant (PDA), also known as a palmtop computer, or personal data assistant, is a mobile device that functions as a personal information manager. PDAs are largely considered obsolete with the widespread adoption of smartphones.

Nearly all current PDAs have the ability to connect to the Internet. A PDA has an electronic visual display, enabling it to include a web browser, all current models also have audio capabilities enabling use as a portable media player, and also enabling most of them to be used as mobile phones. Most PDAs can access the Internet, intranets or extranets via Wi-Fi or Wireless Wide Area Networks. Most PDAs employ touchscreen technology.

The first PDA was released in 1984 by Psion, the Organizer II. Followed by Psion’s Series 3, in 1991, which began to resemble the more familiar PDA style. It also had a full keyboard.

The term PDA was first used on January 7, 1992 by Apple Computer CEO John Sculley at the Consumer Electronics Show in Las Vegas, Nevada, referring to the Apple Newton.

 

Sharp-KDDI-IS01-compact-handheld-computer-android-os-open j568-main

 

Personal computers

A personal computer (PC) is a general-purpose computer, whose size, capabilities and original sale price makes it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator. This contrasted with the batch processing or time-sharing models which allowed larger, more expensive minicomputer and mainframe systems to be used by many people, usually at the same time. Large data processing systems require a full-time staff to operate efficiently.

1desktopcomputers1

 

 

 

 

 

 

 

 

Two main types:

Desktop model – the system unit sits horizontally on a desk and the monitor is placed on top.

Tower model – the system unit is vertical so can be placed on the floor to save desk space.

 

320px-Computer-aj_aj_ashton_01_svg

 

 

 

 

 

 

 

 

Mainframe & Networked Computers

Mainframe Computers

These types of computers are large, fast and expensive. They are used by large organizations  such as banks. It connects hundreds and thousands of users. These users connect via terminals which are located in different cities or even abroad.

Modern mainframe design is generally less defined by single-task computational speed (typically defined as MIPS  rate or FLOPS in the case of floating point calculations), and more by:

  • Redundant internal engineering resulting in high reliability and security
  • Extensive input-output facilities with the ability to offload to separate engines
  • Strict backward compatibility with older software
  • High hardware and computational utilization rates through virtualization to support massive throughput

Their high stability and reliability enables these machines to run uninterrupted for decades.

5

Networked Computers

licence-desktop

  • Personal computers connected to a server via network cards and cables.
  • The software and data is stored on the central server rather than installed individually on each PC.
  • The network also enables a fast Internet connection, printers and scanners to be shared.
  • Users access allocated resources via a user name and password.
  • Very popular with small-to-medium-sized businesses, schools and colleges/adult education centers.

Computer Types

There are many types of computer and each type has its own feature, five of these types are:

  • Mainframe computers
  • Networked Computers
  • Personal Computers
  • Laptop/Notebook Computers
  • Personal Digital Assistants/Handheld Computers

Mainframepda426691heres-a-ridiculously-good-deal-on-a-windows-8-laptop-from-vizioWhy-do-we-network-computers

 

 

 

Fun Facts

pic351% of internet traffic is “non-human”. 31% is made up from hacking programs, spammers and malicious phishing.

pic2A new identification system for the internet launches this week which means there can be trillions of new unique addresses made.

pic1It would take 1,000,000 human brains to store all of the information that can be found on the internet.

sp-it-imgThe first computer was almost 2.5 meters (8ft) high and weighed nearly 30,000kg – more than 600 times heavier than an average computer today.

Programming language

programming-languages-list-computers-infographic-600x600A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs to control the behavior of a machine or to express algorithms.

The earliest programming languages preceded the invention of the computer, and were used to direct the behavior of machines such as Jacquard looms and player pianos. Thousands of different programming languages have been created, mainly in the computer field, and many more still are being created every year. Many programming languages require computation to be specified in an imperative form (i.e., as a sequence of operations to perform), while other languages utilize other forms of program specification such as the declarative form (i.e. the desired result is specified, not how to achieve it).

language_map

 

 

 

 

 

Computer hardware

Computer hardware is the collection of physical elements that constitutes a computer system. Computer hardware refers to the physical parts or components of a computer such as the monitor, mouse, keyboard, computer data storage, hard drive disk (HDD), system unit (graphic cards, sound cards, memory, motherboard and chips), etc. all of which are physical objects that can be touched. In contrast, software is instructions that can be stored and run by hardware.

Your PC (Personal Computer) is a system, consisting of many components. Some of those components, like Windows XP, and all your other programs, are software. The stuff you can actually see and touch, and would likely break if you threw it out a fifth-story window, is hardware.

hw01

 
Not everybody has exactly the same hardware.  Those of you with notebook computers probably have most of the same components. Only in your case the components are all integrated into a single book-sized portable unit.