1. Common to every computer system invented is the file. A file holds a single contiguous block of data. Any kind of data can be stored in a file, and there is no data that cannot be stored in a file. Furthermore, there is no kind of data that is stored anywhere else except in files. A file holds data of the same type, for instance, a single picture will be stored in one file. During production, this book had each chapter stored in a file. It is uncommon for different types of data (say, text and pictures) to be stored together in the same file because it is inconvenient. A computer will typically contain about 10,000 files that have a great many purposes. Each file will have its own name. The file name on a LINUX or UNIX machine can be up to 256 characters long. From Rute-Users-Guide