Okay, some of you are having difficulty understanding precisely what I'm talking about, both here on my 'blog and on my invoices. This is not due to a failure on either persons part; rather, it is a failure in communications.
So for the next few entries, I will try to bring some of the more technical terms I may use to the table and discuss them in more detail.
defrag - DOS and Windows command that invokes the process of defragmentation.
defragmentation - (or defragging) is a process that reduces the amount of fragmentation in file systems. It does this by physically reorganizing the contents of the disk in order to store the pieces of each file close together and in order (contiguously). It also attempts to create larger regions of free space using compaction to impede the return of fragmentation. (from Wikipedia)
file system fragmentation, sometimes called file system aging, is the inability of a file system to lay out related data sequentially (contiguously), an inherent phenomenon in storage-backed file systems that allow in-place modification of their contents. It is a special case of data fragmentation. File system fragmentation introduces disk head seeks, which are known to hinder throughput. (from Wikipedia)
malware - malicious software is software designed to infiltrate or damage a computer system without the owner's informed consent. It is a portmanteau of the words "malicious" and "software". The expression is a general term used by computer professionals to mean a variety of forms of hostile, intrusive, or annoying software or program code. (from Wikipedia)
page file - a file on your hard drive that emulates your computers random access memory (RAM - often the smallest of the vertical chips sticking up from the main computer board inside your tower or CPU). Items in memory that aren't used very often are written to the page file in order to free up space in the much faster RAM. The page file can also act as additional RAM once all of your physical RAM is in use. Since the page file is on the hard disk, transfer into and out of the page file is limited by the speed at which your hard disk operates. Hard disks rely on relatively slow mechanical systems to read and write information, dealing with memory paged to the hard disk is substantially slower than working with memory in the RAM chips. This is why the computer slows down when it is out of physical memory - it must instead perform tremendous amounts of reads and writes on the hard drive that it uses for its memory.