提示 & 技巧

了解病毒

The first tenet of warfare is this: know thy enemy. 那么电脑病毒到底是什么呢? Computer viruses are devious little computer programs that attach themselves to legitimate program hosts and then engage in rampant self-replication. 人们很容易被它们的小尺寸所迷惑. 不要. 它们不会小太久. Computer viruses propagate like rabbits -- and by the time you first recognize their presence, your data may be permanently damaged or erased.

On this point, however, an important clarification must be made. Like biological viruses, computer viruses are not inherently destructive. You're probably harboring a fugitive cold virus in your body right now, 即使你没有生病. With both biological and computer viruses, you can be infected without being affected. Your computer can be a veritable hive of viruses without exhibiting any visible symptoms or actual damage. If not instructed to do otherwise, viruses will quietly, unobtrusively and perpetually replicate. They're only destructive if intentionally engineered to be so.

Malicious computer viruses contain a "payload" -- a programming element separate from the self-replication code that executes its objectives. For example, a payload might display a personalized message on your monitor. 它可能会擦除关键数据或程序文件, 重新格式化你的硬盘, or infiltrate your messaging software and overload the local network with authorless e-mail. 但并非所有的电脑病毒都是一样的. Some are full of sound and fury, yet signify nothing. 还有一些是无声但致命的. In general, though, computer viruses are of three main types:

Macro Viruses: These are the most prevalent type of virus today. Unlike conventional viruses which can attach to virtually any program, 宏病毒以特定的程序为猎物. A macro itself is an instruction code that automatically executes other program commands. Many popular and prominent software applications utilize macros extensively. Essentially, macro viruses are macros that embed within a program and self-replicate.

Macro viruses that run on Microsoft applications like Word and Excel are particularly common -- chiefly because certain programming strategies employed by these applications make them particularly susceptible. Macro viruses work like this: when an infected document is initially opened, the macro virus embeds itself in the associated application and then proceeds to attach itself to every subsequent document created. In this way, the macro virus is unwittingly disseminated whenever the user transfers a document.

Parasitic Viruses: These are the most infectious type of virus. Parasitic viruses attach themselves to executable programs like .com或 .exe文件. 一旦启动受感染的文件, 病毒可以自由地自我复制, 嵌入主存储器, 或者释放它的有效载荷. Further, it can corrupt not just specific programs, but virtually any program being processed in RAM.

Boot Sector Viruses: The boot sector is essential software that resides on hard, 软盘或光盘, and is responsible for loading your operating system into memory at the start of a computing session. Boot sector viruses penetrate this vital boot sector and alter its contents. As opposed to macro viruses, boot sector viruses are spread not by sharing documents, but diskettes. Whenever new diskettes are introduced to a previously infected computer, the boot sector virus is transferred to the healthy diskette, which then conveys the virus to other computers, 等等.......

These are all considered true computer viruses. Another commonly observed form of computer pestilence (though not literally a virus) is the worm. Worms differ from viruses in that they do not require a host to wreak their havoc. 其他病毒被称为特洛伊木马. Trojan Horses are viruses that masquerade as legitimate programs, 文件或其他软件, 之后才会显露出它们真正的功能. Trojan Horse viruses are often spread through e-mail or online bulletin boards.

Certainly no one would knowingly expose their computer to a virus. Unknowingly, however, thousands daily place their machines in peril. Ignorance is no excuse, though -- an ounce of prevention is worth a pound of cure. The following are some common troubleshooting techniques for keeping your computer virus-free:

- Always rely on a reputable anti-virus software application like Norton or McAfee.
- Always scan new files, diskettes or software before loading them on your machine.
- Always back-up critical software or files to avoid permanent loss due to infection or deletion.
- Always be wary of strange operating tics or unusual graphics.
- Always ensure vigilance from the other members on your computer or network.
- Always write-protect your system and program disks.
- Always enable Macro Virus Protection in all Microsoft applications.
- Never share diskettes or software without assuring their integrity.
- Never download e-mail or Internet files/programs without scanning them first.
- Never act on an e-mail virus alert without confirmation from an IT professional or trustworthy resource.
- Never boot your system with a diskette other than the original.