Final answer:
isIRI() and isURI() are functions used in web development to check if a given string is a valid IRI or URI respectively.
Step-by-step explanation:
isIRI() and isURI() are functions used in computer programming, specifically in web development, to check if a given string is a valid Internationalized Resource Identifier (IRI) or URI (Uniform Resource Identifier) respectively.
An IRI is a generic term for a web address that allows non-ASCII characters, while a URI is a more specific term for a web address that only allows ASCII characters.
These functions are used to validate user input and ensure that the input provided is a valid web address before further processing or displaying it on a web page.