Antivirus and data security

Hello students, welcome to Kwickprep. You click a link that promises a free phone, and suddenly your files are locked. What went wrong, and how could you have stopped it? Today we will learn about malware, how antivirus software protects us, and simple habits that keep our data safe.

Let us start with two simple words. Data means any information stored on a computer or phone, like your photos, marks, messages and passwords. Data security means protecting that data from being stolen, changed or destroyed. The main threats are harmful software, people who break into systems, and our own careless mistakes.

Harmful software has a special name. Malware is short for malicious software, which means software written on purpose to cause harm. It can steal your data, delete it, lock it, or quietly spy on you. It usually enters through unknown links, unsafe downloads, email attachments and infected pen drives.

Here are five types of malware that you should know. A virus attaches itself to a file and spreads when that file is opened or shared. A worm copies itself across a network without anyone opening a file. A Trojan pretends to be a useful program, like a free game, but hides harm inside. Spyware secretly watches what you type and do, so it can steal passwords. Ransomware locks your files and demands money, called a ransom, to unlock them.

Now, our main defence. Antivirus software is a program that detects malware and removes it before it can do damage. It checks files, downloads, pen drives and email attachments. But it can only catch the threats it knows about, so it must be updated regularly.

Let us see the steps as a flowchart. A new file arrives, maybe from a download or a pen drive. The antivirus scans the file and compares it with a list of known malware patterns, called signatures. It also watches for suspicious behaviour. If the file matches, the antivirus quarantines it, which means it locks it away safely, or deletes it. If the file is clean, it is allowed to open.

Antivirus programs offer different kinds of scans. Real-time protection is always on and checks files the moment they open or arrive. A quick scan takes a few minutes and checks the places malware usually hides. A full scan checks every file on the computer, so it takes longer. A custom scan checks only what you choose, such as a pen drive a friend gave you.

You do not always need to buy antivirus software. Windows already includes Microsoft Defender, which gives real-time protection for free. Many families also buy security suites from companies like Quick Heal, Norton or McAfee. Do not run two antivirus programs with real-time protection together, because they can clash and slow the computer. And always get antivirus from the official website, because fake antivirus apps are themselves malware.

How can you tell that a device may be infected? The computer suddenly becomes very slow without any reason. Strange pop-ups and ads keep appearing. Files go missing, get renamed or refuse to open. Programs start by themselves, or settings change without you. If you see these signs, disconnect from the internet and run a full scan.

Antivirus is only one layer, so let us build good habits too. Use strong passwords, with letters, numbers and symbols, and a different one for each account. Turn on two-step verification, where you also need a one time password, or OTP, sent to your phone. Keep the operating system, apps and antivirus updated, because updates fix security holes. And back up important files to a pen drive or cloud storage, so ransomware cannot take them away.

Here are four more habits. Do not click links or open attachments from unknown senders, even if they promise prizes. Scan every pen drive before you open its files. Never share your OTP or password, not even with someone who says they are from your bank. And avoid online banking on free public Wi-Fi at a railway station or café.

Pause and think. What should Riya do if money vanishes from her UPI account after she clicked a strange link? Here are the steps. First, disconnect the device from the internet. Next, run a full antivirus scan. Then change passwords using a different, safe device. Finally, report it quickly on the national cyber crime helpline, one nine three zero, or at cybercrime.gov.in.

Let us revise what we learned today. Malware includes viruses, worms, Trojans, spyware and ransomware. Antivirus software scans files, quarantines threats and removes them. It works only when it is kept updated, along with your other software. Strong passwords, two-step verification and backups protect your data. And always think before you click, and report cyber fraud on one nine three zero.