A personal computer (PC) is any general-purpose computer whose size, capabilities, and original sales price make 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.
Software applications for personal computers include, but are not limited to, word processing, spreadsheets, databases, Web browsers and e-mail clients, digital media playback, games, and myriad personal productivity and special-purpose software applications. Modern personal computers often have connections to the Internet, allowing access to the World Wide Web and a wide range of other resources. Personal computers may be connected to a local area network (LAN), either by a cable or a wireless connection. A personal computer may be a desktop computer or a laptop, tablet, or a handheld PC.
While early PC owners usually had to write their own programs to do anything useful with the machines, today's users have access to a wide range of commercial software and free software, which is provided in ready-to-run or ready-to-compile form. Since the early 1990s, Microsoft operating systems and Intel hardware have dominated much of the personal computer market, first with MS-DOS and then with the Wintel platform. Popular alternatives to Microsoft's Windows operating systems include Apple's Mac OS X and the free open-source Linux and BSD operating systems. AMD provides the major alternative to Intel's central processing units. Applications and games for PCs are typically developed and distributed independently from the hardware or OS manufacturers, whereas software for many mobile phones and other portable systems is approved and distributed through a centralized online store.In July and August 2011, marketing businesses and journalists began to talk about the 'Post-PC Era', in which the desktop form factor was being replaced with more portable computing such as netbooks, notebooks, tablets, and smartphones.