Serialization is the process of converting an object or data structure into a format that can be easily stored or transmitted. This format can be a byte stream, a string, or a file, allowing the data to be saved to a disk or sent over a network. Common serialization formats include JSON, XML, and Protocol Buffers. When the serialized data is needed again, it can be deserialized, which means converting it back into its original object or data structure. This is essential for applications that require data persistence or communication between different systems, such as in web services or database interactions.