Streams are classes that let you read and write data. They provide a common interface for reading and writing to different media such as memory, strings, sockets, and BLOB fields in databases. There are several stream classes, which all descend from TStream. Each stream class is specific to one media type. For example, TMemoryStream reads from or writes to a memory image; TFileStream reads from or writes to a file. 

The following topics describe the methods common to all stream classes:

• Using streams to read or write data
• Copying data from one stream to another
• Specifying the stream position and size