It is important to know which type of interface your hard drive and CD-ROM drive have. If you don't know, there is really no easy way to find out. Unless you have an older Macintosh, CD-ROM drive, or you specifically ordered a system with SCSI devices in it, you probably don't have a system with a SCSI interface. If you aren't absolutely sure, it won't matter if you are going to install a newer version of Linux. The newer installation programs for Linux are capable of detecting what type of drive you have.
Most people probably know what RAM is.
This is a much-publicized memory type that a computer uses to have quick access to certain data. The more RAM you have, the better your system will perform. Today's systems need between 48 and 64 Megabytes of RAM, depending on the type of functions the computer is serving. It starts using available hard drive space to store information that the programs need. Let's return to the filing cabinet analogy.