Validation is a computer programming technique used to ensure that data entered into a computer program or application meets a certain set of criteria. Validation is used to protect software from malicious or incorrect data, as well as to prevent errors from occurring in programs. By ensuring that all data meets certain standards, data entered into a computer can be used reliably and without fear of compromising the safety of a program or system.
Validation is typically used to check user input, such as text fields or form data, to ensure that certain values are present, and to check the specific format. Data entered is checked against a set of criteria to ensure that it is valid, complete, and accurate. Depending on the type of validation used, incorrect or invalid data may be rejected and an error message displayed, or accepted but corrected to match the criteria.
Validation can take place on either the client side or the server side. Client-side validation takes place in the user’s browser, and is generally accomplished with JavaScript or other scripting languages. Server-side validation occurs on the web server and is typically accomplished with PHP or other server-side languages. Both instances of validation are used to complement each other, ensuring that any data submitted is complete and traceable.
Validation techniques can be used for a variety of applications and programming languages, from HTML forms to web applications and desktop programs. It is an important part of any system or application development process, as validating user input is integral to creating a secure, reliable experience for the user.
