An Internet bot is a software program that performs tasks over the Internet in an automated manner that is much faster than a person would be able to do. Although it is software, an Internet bot interacts with network services intended for people as if it were a person. Some Internet bots are harmless and useful, but some are dangerous.
A Web crawler is a type of Internet bot used by Web search engines, such as Google and Excite, to surf the web and methodically catalog information from Web sites. Other types of Internet bots install themselves in an unknowing victim’s computer and work as spyware by sending information about the user’s browsing activities and possibly activating when specific words are typed at the keyboard. Even more dangerous versions exist that steal personal information such as credit card data and passwords. Some computer attacks, for example a denial of service attack, may rely on previously installed Internet bots to perform attacks.
- Be careful opening email attachments. Never open a mail attachment when you don’t know who is sending it, and never open it if it is an executable (.exe) file.
- Be suspicious of web advertisements. Watch out when surfing the web. Don’t believe promotions that entice you to open a link or file, such as "You have won a prize. Just click here!"
- Use a pop-up ad blocker.
- Firewall. Use the firewall installed in your computer, or install a personal one in your local machine. A firewall is like a security guard for your computer that monitors the traffic into and out of your computer. When configuring it, limit the outgoing and incoming ports to those you know you will need. Most personal firewalls will prompt you each time a connection is attempted and will adapt their permissions accordingly
- Internet bot(Wikipedia)