Unit 4 | Staying Safe

Viruses

Some other words you might hear people use are virus or malware.

On a computer, these are programs that change things that you don’t want. Often they will try to get into your computer secretly, and then do something bad.

How does a virus work, and what might it do?

A lot of viruses will look and act like a normal program. You can download it from the internet, and then run it like any other program. It might even do the things that it promised to do, such as play a game or open some file.

However, it will often do other things in the background which you can’t see:

• ex. It might send your information to someone else.
• ex. It might break something on your computer, and then tell you that you need to pay money to fix it.
• ex. It might wait for you to type in a password, and then try that password to open other things.

How do I protect myself from viruses?

• Be careful when you download things: The next section will talk about the internet in more detail. Similar to how you might avoid stores that you don't trust, you can also avoid downloading things from websites that you don't trust.
• Leave your antivirus on: Most modern computers and phones will keep an eye out for viruses for you. This should be turned on already, but you can check in the settings to make sure. When they detect a problem, they will tell you and try to fix it.

Example warning messages

Here are some warning messages for Windows computers.

The blue message says that it blocked an unknown program from running. This might happen to a normal program as well, and you can run the program anyways if you trust it. Otherwise, you can ask someone you trust.

The red message says that it found a 'malicious file'. This is more serious, and you should be extra sure that you trust the file before opening it.

Windows warning messages

You might also see warnings from the browser when you are on the internet, such as this one from the Firefox browser. This is a warning that the website you are trying to visit is not safe, and you should not go there.

Firefox warning message

• Don't get an antivirus program from a stranger: These days, you very likely do not need an extra antivirus program. Some places might try to sell you one, or even give you one for free. They might even say that your computer is already "infected" or needs "cleaning". Don't download these programs, as they are often viruses themselves.