What is a verification code It s so annoying, what s going on with sending verification codes all th

What's going on with sending verification codes all the time1Generally speaking, the verification number is only valid if it is correctly sent to the corresponding mobile phone login, if you receive a lot of verification numbers inexplicably, it may be possible or guess that your mobile phone number is leaked due to some group tour reasons; 2.Or due to some reasons, your mobile phone number is bombarded by criminals with text messages, constantly sending verification codes and other spam messages to your mobile phone number; You can try to use third-party mobile phone manager and other software to set up harassment blocking to reduce harassing text messages as much as possible.

Categories: Computer Internet >> Internet.

Problem description: Why do I always have to enter the verification code when I log in or post? Does it do anything? Please advise.

Analysis: 1).Captcha is generally to prevent batch registration, and it looks difficult to the human eye, let alone a machine.

Two like the post bar is not logged in to post to enter the verification code is probably to prevent the occurrence of large-scale anonymous replies At present, many ** in order to prevent users from using robots to automatically register, log in, and irrigate, all use verification code technology. The so-called verification code is to generate a string of randomly generated numbers or symbols, add some interfering pixels (to prevent OCR), and the user will recognize the verification code information by the naked eye, enter the form to submit** verification, and only after the verification is successful can a certain function be used.

2）.Generally, the place where the user ID is registered and the major forums require a verification code.

3）.Common captchas.

1. Four-digit number, a random one-digit string, the most original verification code, the verification effect is almost zero. 2. CSDN** user login is in GIF format, which is currently commonly used as a random number ** verification code. **The characters on the ** are more decent, and the verification effect is better than the previous one.

For those who do not have basic graphic iconography knowledge, it is unbreakable! It's a pity that the program that reads it, on the first day that csdn used it, seems to have been published in the forum, which is really pitiful!

3,QQ**User login is in png format,**Random numbers + random capital English letters,The whole composition is a bit flamboyant,Every time you refresh it,Each character will change its position! Sometimes the ** that comes out can't be recognized by the human eye, it's amazing....4. When MS hotmail is applied, it is in bmp format, random number + random capital English letter + random interference pixel + random position.

5, Google's gmail registration is in jpg format, random English letters + random color + random position + random length. 6. Other major forums are in XBM format, and the content is random.

4) Significance: In order to prevent users from using robots to automatically register, log in, and irrigate, they have adopted captcha technology. The so-called verification code is to generate a string of randomly generated numbers or symbols, add some interfering pixels (to prevent OCR), and the user will recognize the verification code information by the naked eye, enter the form to submit** verification, and only after the verification is successful can a certain function be used.