MacBook - facts from Wiki
The MacBook is a brand of notebook computers manufactured by Apple Inc. from early 2006 to late 2011, and relaunched in 2015. It replaced the iBook series and 12-inch PowerBook series of notebooks as a part of the Apple-Intel transition from PowerPC. Positioned as the low end of the MacBook family, below the premium ultra-portable MacBook Air and the powerful MacBook Pro,3 the MacBook was aimed at the consumer and education markets.4 It was the best-selling Macintosh ever. For five months in 2008, it was the best-selling laptop of any brand in US retail stores.5 Collectively, the MacBook brand is the "world's top-selling line of premium laptops."6
There have been four separate designs of the MacBook. The original model used a combination of polycarbonate and fiberglass casing which was modeled after the iBook G4. The second type was introduced in October 2008 alongside the 15-inch MacBook Pro; the MacBook shared the more expensive laptop's unibody aluminum casing, but omitted FireWire, which hurt sales.7not in citation given A third design, introduced in late 2009, had a polycarbonate unibody casing and no FireWire ports.
The form of a traditional laptop computer is a clamshell, with a screen on one of its inner sides and a keyboard on the opposite. It can be easily folded to conserve space while traveling. The screen and keyboard are inaccessible while closed. Devices of this form are commonly called a 'traditional laptop' or notebook, particularly if they have a screen size of 11 to 17 inches measured diagonally and run a full-featured operating system like Windows 10, OS X or Linux. Traditional laptops are the most common form of laptops, although Chromebooks, Ultrabooks, convertibles and 2-in-1s (described below) are becoming more common, with similar performance being achieved in their more portable or affordable forms.
About computer virus:
A computer virus is a malware program that, when executed, replicates by inserting copies of itself (possibly modified) into other computer programs, data files, or the boot sector of the hard drive; when this replication succeeds, the affected areas are then said to be "infected".1234 Viruses often perform some type of harmful activity on infected hosts, such as stealing hard disk space or CPU time, accessing private information, corrupting data, displaying political or humorous messages on the user's screen, spamming their contacts, logging their keystrokes, or even rendering the computer useless. However, not all viruses carry a destructive payload or attempt to hide themselves?the defining characteristic of viruses is that they are self-replicating computer programs which install themselves without user consent.
Virus writers use social engineering and exploit detailed knowledge of security vulnerabilities to gain access to their hosts' computing resources. The vast majority of viruses target systems running Microsoft Windows,567 employing a variety of mechanisms to infect new hosts,8 and often using complex anti-detection/stealth strategies to evade antivirus software.9101112 Motives for creating viruses can include seeking profit, desire to send a political message, personal amusement, to demonstrate that a vulnerability exists in software, for sabotage and denial of service, or simply because they wish to explore artificial life and evolutionary algorithms.13
Computer viruses currently cause billions of dollars' worth of economic damage each year,14 due to causing system failure, wasting computer resources, corrupting data, increasing maintenance costs, etc. In response, free, open-source antivirus tools have been developed, and an industry of antivirus software has cropped up, selling or freely distributing virus protection to users of various operating systems.15 Even though no currently existing antivirus software is able to uncover all computer viruses (especially new ones), computer security researchers are actively searching for new ways to enable antivirus solutions to more effectively detect emerging viruses, before they have already become widely distributed.16