# Why Verification Code?

Completely Automated Public Turing Test to Tell Computers and Humans Apart (CAPTCHA), commonly known as CAPTCHA, is a publicly-automated program that distinguishes users from computers or people. In the CAPTCHA test, the computer acting as the server automatically generates a question that is answered by the user. This problem can be generated and judged by computers, but only humans can answer them. Since the computer cannot answer the CAPTCHA problem, the user who answers the question can be considered a human.

The above section is selected from Wikipedia. Because too many robots on the Internet are used to snap up and send spam, it is necessary to use technical means to distinguish between humans and non-humans. The earliest distortions have recently evolved into meanings, so some verification codes are not correct. The most recent verification code like 12306 is a counterattack against the scalper party ticketing process.

So it's important to install a captcha program on a blog site to block malicious registration and spam, but it can't be so complicated. Because most of the comments are to find a channel to communicate with the blogger, rather than just buying and buying tickets, if it is too complicated, it will lose some traffic.

For this, Google launched reCaptcha

This was once a captcha tool for electronic books. Now it has been upgraded to V2, which depends on the response time of the mouse, drag speed, time, location, trajectory, number of retries, and so on. These factors can constitute a sampling result or identification characteristics. Based on these characteristics, you can guess that you are a person or something else.

# installation steps

1. Go to Google reCaptcha to apply (requires login to Google account)

Will let you fill in your name, version, and URL and finally agree to their agreement.

When this is all done, you will get a site key and a secret key. (Webpage is useful later)

2. Search for the Google Captcha install and enable in the wordpress plugin.

Then go to the setting and fill in the site key and secret key of your previous page. Here I need to mention the enable Captcha for this column. I canceled the login because I used Mweb to write a blog post on my mobile phone and push it to my blog. If login authentication is enabled, Mweb will not be able to send it to me. Blog. Because it can log in to the blog by account password.

Next, you can see the effect.

This is the effect on the registration page

This is the effect of the comment interface