disk—preparing it so it can be used. Then, copy the DOS files  from  the  distribution  disks  onto  the  hard  disk.  You must follow the steps in the owner/user manual. It may tell you to use a setup command that leads through the process from the display screen. Once installed, DOS will load from this partition every time you turn on the system. If the system has only floppy disk drives, you will make copies of the distribution disks onto new diskettes. If the new diskettes are not formatted, you can use a command (such as DISKCOPY) that will format and copy.  Again,  follow  the  instructions  from  the  start-up  or getting started section of the owner/user manual. If there is a setup command, use it to lead you through the process. Be sure to prepare external labels with the name of the DOS. Write the serial number if there is one, and write WORKING COPY. Be sure you use a felt-tip pen if you are writing on a label already attached to the diskette. Once you have copied and installed DOS, put the original distribution disks in a safe place. Now you are ready to use the microcomputer, but you may need more than  DOS.  DOS  has  many  useful  commands  like  COPY, DELETE, UNDELETE, FORMAT, BACKUP, and so forth. It will even have an editor, usually a line editor, that allows you to create files and edit them line by line. However, its primary jobs are to manage the system and its resources (disks, printers, and so on) and to help you communicate with the computer to use other programs (application  software). User/Applications   Software When  installing  a  user/application  software package on a system, you need to provide the software with   information   about   your   microcomputer   con- figuration. Because there are so many different software packages and programs available and each one has different requirements, there is no need to go into great detail  here.  Remember,  refer  to  the  documentation–it should provide what you need to know. Many of the manuals lead you through step by step. Backing Up Distribution (Original/Master) Diskettes The first thing you should do is copy the files from the distribution diskettes. Each software package may have several diskettes. If you have a hard drive system, you may copy the files from the distribution diskettes to the hard drive, using the copy command in the operating system. First, set up the name of the directory in which you want to store the tiles. Then copy them to the hard disk. If your system has no hard drive, copy the files to other diskettes. Most operating systems have a copy command that allows you to copy all files on a diskette with a single command. This is called a wild card copy. The copies will become your working copies. Prepare external  labels  for  the  working  copies.  Store  the distribution diskettes in a safe place away from the microcomputer in case you need them in the future. BACKING UP TEXT/DATA FILES In  addition  to  making  backup  copies  of  your distribution diskettes, be sure to backup your text/data files (correspondence, releases, etc.) on diskettes as well. If you lose all or part of your data, the only person to blame is yourself. Data can be lost or damaged in a number of ways. Common causes of data loss are power surges and drops, power failures, hard drive malfunctions and user errors. User errors top the list. Although less common, fire, theft,  vandalism  and  natural  disasters  are  potentially disastrous. How often have you come close to erasing a file or formatting a floppy or hard disk by accident? Probably more times than you care to admit. No matter how many precautions  you  take,  you  cannot  prevent  all  the potential ways data can be lost. You can certainly reduce their  adverse  effects  by  backing  up  your  files  on  a regular basis. When working with data files, at least back them up on a daily basis either to tape, diskette or to another hard disk. No matter how many backups you make (two, three or one for every day of the week) or what method you use  to  make  them,  they  are  worthless  if  they  are destroyed along with your microcomputer. You need to make multiple backups and store a set in a different area away from your working area or at a minimum in a data safe. This will require some extra effort, but it will more than pay for itself should you ever experience a data loss. LOCAL-AREA NETWORKS (LANS) The microcomputer has put the power of mainframe computing  onto  your  desktop  via  local-area  networks (LANs). LANs consist of nodes that are interconnected by links. These nodes and links usually cover a relatively small geographical area, ranging from a few feet to a mile.  Nodes  are  the  hardware,  such  as  computers, terminals, hard disks, printers, and so on. Links are the 1-54