The largest and heaviest type of laptop, desktop replacements are designed to deliver the power and features you'd get from a desktop PC. Too bulky for anything but room-to-room travel within a house or an office, desktop replacements typically offer the best performance, the largest screens and keyboards, and the most complete set of features available on a laptop. Popular among home and business users, these systems can deliver enough computing muscle for serious gaming, multimedia authoring, and even high-level digital audio and video work.
In brief-
A desktop computer is difficult to carry or remove.There are severel separate parts-monitor,Keyboard,Ups-are connected with CPU box that contains Motherboard,processor,Ram,Hard disk.--To carry or to remove desktop computer you have to disconnect monitor,Keyboard,Ups from CPU box and carry them separately .
But a notebook pc or laptop computer is easy to carry with its less weight (2 to 3kg)& smaller size& consume less power.Also it can run on rechargeble battery that provide power to run your laptop for 3 to 12 hours(model depended).
As notebook pc or laptop computer is advantegious in regard of portability and smaller size,it has to sacrifice some computing power,in simple word you can't expect high gaming,graphics,processing performance in laptop just like desktop computer.
But what if we don't need much portability.We can consider some weight and size and get a computer that is the combination of desktop and laptop.Thus it can perform just like a desktop computer and more or less it is portable-with more weight and bigger size than typpical thin laptop.
-----This type of laptop computer is called DESKNOTE computer.
Now I have collected some related articles from websites.You can go through them for detail-
A desktop replacement computer (dtr) is a personal computer that provides the full capabilities of a desktop computer while remaining mobile. They are often larger, bulkier laptops. Because of their increased size, this class of computer usually includes more powerful components and a larger display than generally used in smaller portable computers and can have a relatively limited battery capacity (or none at all). Some use a limited range of desktop components to provide better performance at the expense of battery life. These are sometimes calleddesknotes, a portmanteau of the words "desktop" and "notebook," though the term is also applied to desktop replacement computers in general.
Origins
The forerunners of the desktop replacement were the portable computers of the early-to-mid 1980s, such as the Osborne I, the Compaq Portable and the Commodore Executive 64 (SX-64) computers. These computers contained the CPU, display, floppy disk drive and power supply all in a single briefcase-like enclosure. Similar in performance to the desktop computers of the era, they were easily transported and came with an attached keyboard that doubled as a protective cover when not in use. They could be used wherever space and an electrical outlet were available, as they had no battery.
The development of the laptop form factor gave new impetus to portable computer development. Many early laptops were feature-limited in the interest of portability, requiring such mobility-limiting accessories as external floppy drives or clip-on trackball pointing devices. The first laptop that could be used as an only computer was the PowerBook 500 series, with its built in ethernet, video, SCSI, ADB and serial ports, it duplicated the functionality of the desktop models.
The development of the modern desktop replacement computer came with the realization that many laptops were used in a semi-permanent location, often remaining connected to an external power source at all times. This suggested that a market existed for a laptop-style computer that would take advantage of the user's reduced need for portability, allowing for higher-performance components, greater expandability, and higher-quality displays. Desktop replacement computers are also often used with a docking station, to fully enjoy the desktop comfort.
Design features
Modern desktop replacements generally perform better than traditional laptop-style computers as their size allows the inclusion of more powerful components. The larger body means more efficient heat-dissipation, allowing manufacturers to use components that would otherwise overheat during normal use. Furthermore, their increased size allows for greater expandability and features, as well as larger and brighter displays. However, these advantages generally come at a price premium, with many computers in this class costing as much as two desktop computers with similar specifications.
Using a laptop form factor, however, desktop replacements still often suffer from limitations similar to those of more mobile laptops. They usually lack the ability to accept standard PCIexpansion cards, limiting their expandability somewhat. While the computers can offer slightly better cooling than other laptops, they rarely dissipate heat efficiently enough to allow for high-end desktop-class components, and thus may not reach the same performance levels as desktop computers.
Desktop replacement computers are, with a few exceptions, difficult to upgrade compared to desktop computers, with many of their major components (such as the display) integral to the design of the machine, and others (such as the CPU and GPU) often being hard to access and replace. A small segment of desktop replacements do not include a battery as a standard feature, while some do not include PC-Card support. They have the same limitations on serviceability as laptops, and can rarely use identical components to a desktop computer.
