A more common role is that, as a WEB site, sometimes it will be maliciously attacked by others. That is, identity spoofing. By writing scripts on the user’s client, the user repeatedly logs in or publishes spam information, which eventually causes the website to crash or a large number of spam advertisements.
Because it is easier for people to recognize the text or numbers of pictures. As an attacker, it is difficult to identify the verification code. This ensures that only one person is accessed, not the machine. By adding interference information to it. This ensures that the verification code is not easily recognized by the machine.
There is also a verification code that increases with the competition for Internet platforms. The platform is designed to attract more users. Various promotions have been launched. But in order to avoid individual malicious registration to obtain benefits. Add unnecessary extra costs. The platform introduced a mobile phone verification code. A mobile phone number corresponds to a registered user. This avoids duplicate registrations. Protect the interests of the platform.
But sometimes, when we register for some websites. There is only one mobile number. I want to register more trumpet. Or for some reason. Need to bind some accounts. Or need to use a mobile phone verification code. At this time, you can receive SMS online at Receive-sms-free.net for free.