Entering that randomly-generated code before sending out a form.

[macaddict23]

I've always wondered if it's necessary. If so, how does one implement it on a web page? Thanks.

 

[CanadaRAM]

It's necessary only if you want to protect yourself from the form being used by spam-bots.

 

[angelwatt]

It's not necessary, but can cut down on the spam sent from such forms. Just do some searching for CAPTCHA. There's several products that do it that you can make use of. It's generally more important for more popular sites that spammers are specifically targeting, and for forms that are used for creating accounts and such. I use a variant of CAPTCHA on my feedback form and keeps spam away, but I only get very few attempts from spambots (3-4 a week). Depending on the form it's a good idea to set the meta tag for the page to not cache, which reduces (though doesn't eliminate) the number of spambots that find the page.

 

[jonnylink]

You can write your own using php pretty easily. Or you can try reCAPTCHA (see also).

 

[jakeOSX]

i highly recommend recaptcha, it is easy to use, and it has a secondary (good!) use as well.

and, it cut my spam postings to practically nil.

practically.

(hey, they were pretty high)

 

[mkrishnan]

i highly recommend recaptcha, it is easy to use, and it has a secondary (good!) use as well.

I think the idea of it is neat. I'd bitch a lot less (close to zero ) about those text entry things if they used that software and book texts.

 

[mnkeybsness]

There are actually many ways to keep yourself from getting spammed without the use of captcha.

• Always require email addresses and verify they were formatted correctly.
• Check for HTML, BBCode and other markup styles, as spammers love to try those
• Check for multiple URLs and Email Addresses in subject lines and body text.

The one thing that people need to realize is that no method is fool-proof and the more security checks you put in for the user to do, the harder it is for them to get their task done.

I've tried signing up for things before that had Captcha methods during the signup process and actually gave up because I failed the captcha every time.