How Does CAPTCHA Work? | By Techquickie

The above goes through one of the most popular validation methods - CAPTCHA. This is used to ensure that the person entering a form is 'not a robot' and is indeed a human.

What Are Validation Techniques?

Validation techniques are methods to ensure that data entered on online forms are correct and up-to-date. Validation techniques are important because data is valuable to organisations and incorrect data is useless. There are organisations in Australia with the main purpose of collecting and selling data for marketing purposes.​

What are some Validation Techniques?

Below are examples of validation techniques that can be performed to ensure data is correct:

• Range Check - checks that numbers entered are within a defined range, for example checking the date of birth for an age-restricted website.

• Field Check - checks that all required fields have been entered. Required fields are often symbolised with an asterisk (*).

• Length Check - checks that the entered fields don't exceed a defined limit, such as a character limit or word limit.

• Email verification - checks the entered email address is legitimate.

• CAPTCHA - checks that the person entering the online form is a human and not a robot.