Serialization and deserialization in Java are processes that enable the conversion of Java objects into a byte-stream representation and vice versa. Serialization transforms an object into a sequence of bytes, which can be easily stored in files or transmitted over a network. This is essential for persisting object states or sharing data between different systems. Deserialization, on the other hand, reconstructs the original object from the byte-stream, allowing the application to retrieve and utilize the object’s data. These mechanisms are crucial for various Java frameworks, but they also pose security risks if untrusted data is deserialized improperly.