This is Computer Viruses and Threats explained by Common Craft
本期介绍电脑病毒及预防。

You've probably been sick before. It's not fun.In many cases, like the flu, you're sick because of a virus…tiny germs ready to multiply and spread from person-to-person, via handshakes or sneezes.
你肯定生过病吧，很不爽，对吗?生病通常是因为感染了病毒。握手、打喷嚏都能让病毒繁殖传播。

Computer viruses are no different.Instead of germs, they are computer programs.These programs are usually designed by criminals to multiply and spread from computer-to-computer like a disease.If one makes it to your computer, it can erase your files, send emails without your permission or even communicate sensitive info to criminals.
电脑病毒亦然。但不是微生物而是电脑程序。黑客设计的病毒程序会像疾病一样在电脑间传播一旦电脑感染了病毒，它会删除文件、私发邮件、甚至把私人信息泄露给犯罪分子。

Let's take a closer look, because what we call computer viruses can actually be viruses, worms or trojans. We’ll start with viruses.These bugs hitch a ride when something, like a file, is shared between computers. This often happens via attachments sent in email or shared USB drives.Once someone clicks to open the file, the damage is done.The virus is now on that computer, where it starts to multiply and look for chances to hitch a ride to a new computer.
电脑病毒可以细分为三种，普通病毒、蠕虫 、木马先来说说普通病毒。它通过电脑之间的文件共享来传播。通常会在附件或U盘中出现，一打开这种文件，电脑就会中毒。然后复制，等着感染下一台电脑。

Like a sick human, it’s sometimes hard to to tell when a file has a virus.For this reason, the best defense is anti-virus software.It prevents viruses from getting to your computer and removes them when they are found.
和人生病一样，有时候文件是否感染病毒也很难”确诊”。所以，最好的防护措施就是安装杀毒软件能防止电脑中毒，也能在发现病毒时及时清除。

Now, worms are a little scarier.They are programs that spread to computers without humans doing anything.Criminals create worms to spread via computers that are connected in a network. They worm their way from computer-to-computer automatically.Whether it's a small office or a global network like the Internet.
蠕虫则更可怕，即使我们什么也没操作，它也能传播。只有电脑联网，蠕虫就会感染网上的病毒。不管是局域网，还是在整个互联网中。

Usually, the worms find a back door.a way to trick the computer’s software into letting them in.Once they're in, they look for the same backdoor in similar computers,wreaking havoc along the way.
蠕虫擅长走”后门”。就是通过电脑软件的漏洞入侵。一旦被感染，蠕虫还会寻找其他电脑的”后门”，一路披荆斩棘地破坏下去。

The best defense is keeping your computer software up to date at work and home.This helps close the doors and prevent problems.
最好的防护措施是，更新系统、修复漏洞，门关好了，蠕虫就爬不进来了。

Trojans, our last example, are sneaky bugs.Like the real trojan horse, they’re a trick.If you fall for it, you end up downloading a virus from the Internet.It may appear to be a game or useful software, but hidden inside is a program that can cause problems.For example, these programs can open new backdoors,giving criminals access to your computer and information over the Web.
木马则是最最阴险狡诈的病毒。像传说中的特洛伊木马，它也善用诡计，一个不小心就可能从网上下载木马。木马病毒会伪装成游戏或者常用软件，有些木马还会给电脑开新的”后门”，让犯罪分子轻易侵入你的电脑获取信息。

Not fun.To avoid trojans, only download software from sites you trust.Just like washing your hands and covering your cough,you have to be aware of what causes problems to avoid them.
可怕吧?要防木马，你必须只在信任的网站上下载软件，提高警惕，时刻注意网络安全，就像咳嗽要掩口，饭前便后要洗手一样。

Keep your computer up to date and get anti-virus software.It will help prevent problems and help you recover.And please…don't click on links, attachments and downloadable you know they're legit.
还要经常更新电脑软件，安装杀毒工具。一边防患于未然，一边“亡羊补牢”。另外，陌生的链接、附件、文件也不要碰。除非能确认它们的安全性。

Through a little awareness, you and your computer will stay happy and healthy.
警钟长鸣，健康常伴。

I’m Lee LeFever and this has been Computer Viruses and Threats Explained by Common Craft.
这就是电脑病毒及预防，我是《原来如此》的李•勒菲弗。