For the third consecutive year, U. The impressive growth was the fastest sales increase since the end computer input output devices pdf the recession. Sales growth accelerated in the second half of the year peaking in fourth quarter with a 6.
9 percent increase over the fourth quarter of 2012. There are a number of different types of computer system in use today. PC, is one of the most common types of computer due to its versatility and relatively low price. The computer case encloses most of the components of the system.
It provides mechanical support and protection for internal elements such as the motherboard, disk drives, and power supplies, and controls and directs the flow of cooling air over internal components. The case is also part of the system to control electromagnetic interference radiated by the computer, and protects internal parts from electrostatic discharge. Large tower cases provide extra internal space for multiple disk drives or other peripherals and usually stand on the floor, while desktop cases provide less expansion room. Portable and laptop computers require cases that provide impact protection for the unit.
A current development in laptop computers is a detachable keyboard, which allows the system to be configured as a touch-screen tablet. DC power for the internal components of the computer. Laptops are capable of running from a built-in battery, normally for a period of hours. The motherboard is the main component of a computer. Many modern computers have the option to overclock the CPU which enhances performance at the expense of greater thermal output and thus a need for improved cooling. CPU and the other components of the system, including main memory.
RAM until the web browser is closed. 2GB, 4GB, and 8GB, but can be much larger. CPU to various internal components and to expand cards for graphics and sound. This battery is generally a watch battery. More powerful graphics cards are better suited to handle strenuous tasks, such as playing intensive video games. Expansions cards can be used to obtain or expand on features not offered by the motherboard.