What validation type ensures that data correctness checks are performed immediately upon data entry?

Client-side validations are designed to ensure that data correctness checks are carried out immediately as the user enters data into a form on a web page. This type of validation runs in the user's browser before the data is sent to the server, allowing for instant feedback. For example, if a required field is left empty or an invalid format is entered, the validation scripts can provide immediate prompts or error messages, encouraging the user to correct their input right away. This enhances user experience by preventing unnecessary server calls and reducing the amount of back-and-forth communication needed to fix user errors.

While server-side validations occur after form submission and are essential for data integrity, they do not provide real-time feedback to the user. Input validations is a broader term that encompasses various validation methods, including both client-side and server-side. Pre-submission validations can also refer to checks performed before the data is sent to the server, but this term is not as commonly used as client-side validations in the context of immediate user feedback.