# Great post on 'Human Interactive proofs' or those screwy letter things where you have to type in some letters... ## Great post on 'Human Interactive proofs' or those screwy letter things where you have to type in some letters... posted on Thursday, September 23, 2004 11:23 PM [Stephen Toub](http://weblogs.asp.net/toub/) has [just posted](http://weblogs.asp.net/toub/archive/2004/09/23/233607.aspx) that he's had an [article](http://msdn.microsoft.com/asp.net/using/building/web/default.aspx?pull=/library/en-us/dnaspp/html/hip_aspnet.asp) go live on MSDN which has some really stunning applications of the '[CAPTCHA](http://www.captcha.net/)' technique for proving that people entering data are really human (or really smart animals I guess). This is simply the [most complete article](http://msdn.microsoft.com/asp.net/using/building/web/default.aspx?pull=/library/en-us/dnaspp/html/hip_aspnet.asp) on the topic for ASP.NET I've ever seen! Great work Stephen!