Stream types refer to the different categories of data streams used in computing and programming. The main types include input streams, which allow data to be read from a source, and output streams, which enable data to be written to a destination. These streams can handle various data formats, such as text or binary, and are essential for tasks like file handling and network communication. Another classification of stream types is based on their behavior, such as byte streams and character streams. Byte streams process data in raw byte format, making them suitable for binary data, while character streams handle data as characters, which is ideal for text. Understanding these types helps developers manage data efficiently in their applications.