What makes a Key Derivation Function different from other families of secure hash functions (like the SHA family of algorithms) that have been investigated before?

Introduction :

A key derivation function (KDF) is a cryptographic algorithm used to derive a cryptographic key from a source of random data, also called a "secret". The derived key can be used for various purposes, such as encryption, authentication, and secure communications. KDFs are designed to be computationally secure, meaning that it is computationally infeasible to derive the original secret from the derived key. KDFs are commonly used to create strong, unique cryptographic keys from passwords or passphrases.