Make your PC hacker-proof

Internet security is a complex subject. Here are some key terms and concepts for PC users to know.

Denial-of-service (DoS) attack: Flooding an IP address with data, causing computers to crash or lose their connection to the Internet. Most DoS attacks are aimed at large Web servers, with the objective of rendering the target site unavailable to other visitors.

Distributed denial-of-service (DDoS) attack: Using multiple computers to launch a DoS attack. A hacker commandeers several outside computers and uses them as platforms to launch the attack, magnifying its intensity and cloaking the hacker's identity.

Hacker: Someone who deliberately gains access to other computers, often without a user's knowledge or permission. Malicious hackers do this to steal valuable information, disrupt service, or cause other damage.

IP (Internet Protocol) address: The identifying number of a computer or other device. Two machines connected directly to the Internet cannot have the same IP address at the same time. Computers with static IP addresses (most systems with DSL or cable modem connections) always use the same IP address; those with dynamic addresses (most systems with dial-up connections) are assigned a new IP address each time they log on to the Internet.

Personal firewall: Software that keeps unauthorised users from accessing a stand-alone PC. It also prevents malicious programs from sending data out.

Port: An electronic connection that allows data to travel between a client PC and a server over a network.

Port scan (or port probe): Data sent by a hacker over the Internet to locate a PC or network and determine whether it has open ports that will accept a connection.

Stealth mode: A protective setting that hides a port so it isn't visible over the Internet. A port that has been put into stealth mode will give no reply to a port scan, thereby providing no evidence that a computer exists at the scanned IP address.

Trojan horse: A malicious program masquerading as something harmless, usually an e-mail attachment or a download that you open and run. A Trojan horse opens your computer to incursions by a hacker.

Join the newsletter!


Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Jeff Sengstack

PC World
Show Comments

Brand Post

Most Popular Reviews

Latest Articles


PCW Evaluation Team

Tom Pope

Dynabook Portégé X30L-G

Ultimately this laptop has achieved everything I would hope for in a laptop for work, while fitting that into a form factor and weight that is remarkable.

Tom Sellers


This smart laptop was enjoyable to use and great to work on – creating content was super simple.

Lolita Wang


It really doesn’t get more “gaming laptop” than this.

Jack Jeffries


As the Maserati or BMW of laptops, it would fit perfectly in the hands of a professional needing firepower under the hood, sophistication and class on the surface, and gaming prowess (sports mode if you will) in between.

Taylor Carr


The MSI PS63 is an amazing laptop and I would definitely consider buying one in the future.

Christopher Low

Brother RJ-4230B

This small mobile printer is exactly what I need for invoicing and other jobs such as sending fellow tradesman details or step-by-step instructions that I can easily print off from my phone or the Web.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?