Type of computer
Desktop computer
A desktop computer is a personal computer designed for regular use at a single location on or near a desk or table due to its size and power requirements. The most common configuration has a case that houses the power supply, motherboard (a printed circuit board with a microprocessor as the central processing unit (CPU), memory, bus, and other electronic components), disk storage (usually one or more hard disk drives, optical disc drives, and in early models floppy disk drives); a keyboard and mouse for input; and computer monitor and printer for output. The case may be oriented horizontally and placed atop a desk or vertically and placed underneath or beside a desk.
An all-in-one desktop computer typically combines the case and monitor in one unit.
Laptop computer
A laptop, often called a notebook or "notebook computer", is a small, portable personal computer with a "clamshell" form factor, an alphanumeric keyboard on the lower part of the "clamshell" and a thin LCD or LED computer screen on the upper portion, which is opened up to use the computer. Laptops are folded shut for transportation, and thus are suitable for mobile use. Although originally there was a distinction between laptops and notebooks, the former being bigger and heavier than the latter, as of 2014, there is often no longer any difference. Laptops are commonly used in a variety of settings, such as at work, in education, and for personal multimedia and home computer use.
A laptop combines the components, inputs, outputs, and capabilities of a desktop computer, including the display screen, small speakers, a keyboard, pointing devices (such as a touchpad or trackpad), a processor, and memory into a single unit. Most 2016-era laptops also have integrated webcams and built-in microphones. Some 2016-era laptops have touchscreens. Laptops can be powered either from an internal battery or by an external power supply from an AC adapter. Hardware specifications, such as the processor speed and memory capacity, significantly vary between different types, makes, models and price points. Design elements, form factor, and construction can also vary significantly between models depending on intended use. Examples of specialized models of laptops include rugged notebooks for use in construction or military applications, as well as low production cost laptops such as those from the One Laptop per Child organization, which incorporate features like solar charging and semi-flexible components not found on most laptop computers.
Portable computers, which later developed into modern laptops, were originally considered to be a small niche market, mostly for specialized field applications, such as in the military, for accountants, or for traveling sales representatives. As portable computers evolved into the modern laptop, they became widely used for a variety of purposes.
Handheld computer
A mobile device is a small computing device, typically small enough to be handheld (and hence also commonly known as a handheld computer or simply handheld), having a display screen with a miniature keyboard (either alphabetic, numeric or alphanumeric) and, in some models, a touchscreen which enables the user to use a "virtual keyboard" that is displayed on screen, along with other icons and "buttons" that can be pressed. Mobile devices typically weighing less than 2 pounds (0.91 kg).[citation needed] A handheld computing device has an operating system (OS), and can run mobile apps. In the 2010s, most handheld devices are also equipped with Wi-Fi, Bluetooth, near field communication (NFC) capabilities and Global Positioning System (GPS) capabilities. They can usually be connected to the Internet and other devices, such as an automobile or a microphone headset or they can be used to provide location-based services. Also, these devices can usually be used to take digital snapshotsand play digital video or audio. Some mobile devices have cellphone capabilities, enabling the user to make phone calls and send text messages. Stable battery power is typically provided by a lithium battery. There are a range of mobile devices designed for different users and target markets; as such, not all mobile devices have the same capabilities.
Early pocket-sized devices were joined in the late 2000s by larger but otherwise similar tablet computers. Input and output of modern mobile devices are often combined into a touch-screen interface. Smartphones and PDAs are popular among those who wish to use some of the powers of a conventional computer in environments where carrying one would be impractical. Enterprise digital assistants can further extend the available functionality for the business user by offering integrated data capture devices like barcode, RFID and smart card readers. Manufacturers that produce these types of devices include Samsung, Sony, HTC, LG, Motorola Mobility and Apple. Increasingly, 2010-era mobile devices also contain sensors like accelerometers, compasses, magnetometers, or gyroscopes, allowing detection of orientation and motion. Mobile devices may provide biometric user authentication, such as using the built-in camera for face recognition or using a fingerprint sensor for fingerprint recognition.
Tablet computer
A tablet computer, commonly shortened to tablet, is a thin, flat mobile computer with a touchscreen display, which is usually in color, processing circuitry, and a rechargeable battery in a single device. Tablets often come equipped with sensors, including digital cameras, a microphone, and an accelerometer, so that images on screens are always displayed upright. The touchscreen display uses the recognition of finger or stylus gestures to replace the mouse, trackpad and keyboard used in laptops.
Tablets are typically larger than smartphones or personal digital assistants with screens 7 inches (18 cm) or larger, measured diagonally. However much of a tablet's functionality resembles that of a modern smartphone, like having a virtual keyboard or running a dedicated 'mobile' operating system.
Tablets can be classified according to the presence and physical appearance of keyboards. Slates and booklets do not have a physical keyboard, and text input and other input is usually entered through the use of a virtual keyboard shown on a touchscreen-enabled display. Hybrids, convertibles and 2-in-1s do have physical keyboards (although these are usually concealable or detachable), yet they typically also make use of virtual keyboards. Most tablets can use separate keyboards connected using Bluetooth.
The format was conceptualized in the mid-20th century (Stanley Kubrick depicted fictional tablets in the 1968 cult film 2001: A Space Odyssey) and prototyped and developed in the last two decades of that century. In April 2010, Apple released the iPad, the first mass-market tablet to achieve widespread popularity. Thereafter in the 2010s, tablets rapidly rose in ubiquity and became a large product category used for both personal and workplace applications.
