An agent is a type of software program that is instructed to go out onto the Internet and perform a specific function on behalf of a user.
The most common type of agents are programs called spiders, which roam the Internet, collecting and indexing its content and creating their own searchable databases of the content found. Search engines use this information to generate search results. Other uses for agents include such things as checking and organizing your incoming email messages, searching airline sites to compare prices, scanning job boards to compile a list of jobs tailored to your experience, or creating customized news feeds.
Frequently Asked Questions
Do I need to use an agent?
Chances are, if you use the Internet at all, you’ve used agents without even realizing it. If you have a smartphone, you’re probably using agents all the time. For instance, an email agent periodically checks your email server, downloads new messages, and organizes them based on parameters you’ve set. You don’t ever have to tell it to do that for you. Your smartphone periodically checks weather services for you and provides sever weather alerts. If you have a shared calendar, your phone and computers periodically check that service, provide updates, and download any new events. Online storage services, like Dropbox, work in much the same automated way. If you receive alerts to price drops at your favorite online retailer, chances are a software agent is behind those too.
Why do some web forms make me prove I’m human?
While agents can be very useful, they can also be used for less desirable activities, such as compromising web servers or distributing spam. In such cases, a software agent may be used to fill out any type of form it finds, searching for vulnerabilities in the server or trying to post a link to spam content on the site. Some marketers also use such agents to promote their services to website owners. By asking you to enter text or numbers you seen in a picture, the website can reduce the chances of a software agent successfully completing the form.
Are agents safe?
In most cases, agents are perfectly safe and can save us a great deal of time and effort by doing tedious or repetitive tasks automatically for us. However, they can also be exploited to do harm. Some forms of malware, once installed on your computer, can activate itself and automatically track your keystroke or search your computer for passwords or other personal information, and then send that information to another server. Software agents known as bots are also commonly used for denial-of-service (DoS) attacks. By simultaneously visiting a webserver from multiple IP addresses (usually thousands or even millions), the bots can flood a server so that it is no longer able to handle the traffic. For most users, keeping your computer and browser up-to-date, and always having updated security software, such as antivirus and firewall protection, is the best way to protect yourself against malicious software agents.