How do you let people create user accounts or post comments on your Web site without letting spam bots in? Simple — make your users prove they’re human. Many Web sites use CAPTCHA (Completely ...

If you use the Web, you have probably encountered an annoying invention called a CAPTCHA. They're the squished-up, stretched and squiggled, color-blotched collections of letters that often must be ...

MUMBAI, India — Faced with stricter Internet security measures, some spammers have begun borrowing a page from corporate America’s playbook: they are outsourcing. Sophisticated spammers are paying ...

Before the presidential election in 1996, a computer company called Digital Equipment Corporation set up a website for opinion polls. There was one problem, though: Partisan hackers could use bots to ...