In Java, File I/O (Input/Output) is a crucial aspect of programming that allows developers to read from and write to files. The Java I/O API provides a comprehensive set of classes and methods to facilitate these operations, primarily organized into two categories: byte streams and character streams.

The java.io package is the traditional library for file handling, which includes classes like FileInputStream, FileOutputStream, FileReader, and FileWriter. FileInputStream and FileOutputStream are used for reading and writing binary data, making them suitable for files like images and audio. In contrast, FileReader and FileWriter are designed for handling text files, automatically managing character encoding, which is essential for correctly interpreting text data ²⁵.

Additionally, the java.nio package, introduced in Java 1.4, offers improved performance and scalability for file operations. It includes classes like FileChannel and ByteBuffer, which provide more advanced features for file handling ².

For effective file operations, it is recommended to use the try-with-resources statement to ensure that file streams are properly closed after use ².