CompareValidator
Compares the value of one input control to the value of another input control or to a fixed value
CustomValidator
Allows you to write a method to handle the validation of the value entered
RangeValidator
Checks that the user enters a value that falls between two values
RegularExpressionValidator
Ensures that the value of an input control matches a specified pattern
RequiredFieldValidator
Makes an input control a required field
ValidationSummary
Displays a report of all validation errors occurred in a Web page