What' s definition of laptop? (Wikipedia)
A laptop, often called a notebook, is a portable personal computer with a clamshell form factor, suitable for mobile use. Although originally there was a distinction between laptops and notebooks, the former being bigger and heavier than the latter, in modern usage 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.
A laptop combines the components and inputs of a desktop computer, including the display, speakers, a keyboard, and pointing devices (such as a touchpad or trackpad) into a single unit. Most modern-day laptops also have integrated webcams and built-in microphones. The device can be powered either from a rechargeable battery or by mains electricity from an AC adapter. Laptops are diverse devices and specialised kinds, such as rugged notebook or convertible computers, have been optimized for specific uses. The hardware specifications significantly vary between different types, makes, and models.
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 accountancy, or for sales representatives. As portable computers became closer to the modern laptop, they became widely used for a variety of purposes.
Computer - necessary?
At present it is difficult to imagine life without a computer. It is necessary to work - in every office, in every bank, in every school and institution. Around computers developed into the most profitable industry - IT. It covers not only issues of hardware, but also software, or related to the Internet and any use of new technologies. IT professionals is one of the richest group and possibly it won't change in the future. We are not able to imagine life without the Internet, we have to unlimited access to the virtual world. Remember that the smartphone and tablet devices are type of computers too - they have their own processors, graphics chips, etc. We are completely addicted from technology - that's true.
Computer virus - some facts:
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