CYBER NOTES by Dave Benore

What in the world are these things called computer files—what do they do--and

why do we care?

Computer files are something every user should grasp well. I’ve noticed that a number of computer users do not have a good understanding of what they are and what they do. So here goes my explanation.

A file is merely a collection of data or instructions held (filed) under a name—so it can be found when needed. They contain the total information in a computer’s memory—the one that doesn’t forget even when the computer is off.

Think of a book. A book is a collection of words, numbers and symbols that have meaning for us, the readers. It is written in a language (code) that humans understand. It contains information (even if it’s a novel). In other words, a book is a collection of data or instructions bound together and bearing a name.

When we want to find a book we look for its name, not for the words in it. If we don’t know its name we have to look it up, or find the name by some other means. Computers do exactly the same thing. When they want to find some information they look for a certain file (“computer book”) to find it. And computer files are in a “code” (language) that the computer can understand. So you might say that computer files are the computer’s form of a human’s books. Just as books can be short or long, computer files can be short or long.

So what is in these files? The same thing as in humans’ books—information. Human books can contain instructions for humans to follow, such as in math books, or cook books, or repair manuals. Computer files can contain instructions for a computer to follow. In this case the file is called a program file.

Sometimes human instructions for a certain task use more than one book. So too, computers may use more than one program file in executing certain tasks. Then the collection of program files is called simply “the program”. An example is a word processor program. The program may have literally tens or hundreds of separate program files in its makeup.

The other basic type of computer file is a data file. Like some human books that contain only “facts” with no instructions, data files do not tell a computer what to do. No instructions, only “facts” (data). An example might be a letter written to Aunt Jane. It has no instructions for the computer, only “data”. And in fact, the data has no relevance for the computer, only for humans. (There can be data files that have relevance for a computer and not for a human. These are files that contain information the computer uses to “set itself up”—the boot up process. These are frequently referred to as configuration files.)

The output of our work with a computer—examples of output might be a letter, or a tax return, or an investment portfolio—are all stored within data files. The computer can only act on these files by using “programs”. Programs give the computer the instructions on how to process our data files and how to display them for us. Displaying them is the process whereby a computer converts a file’s information from computer code to “human” code—English for example.

Data is given to the computer by inputting it from the keyboard, by reading a floppy or CD-ROM disk, or by reading from data files already stored on the computer. (By the way, CD-ROM stands for compact disk-read only memory.) The program we select, like a word processor, operates on the data we have selected according to instructions from the program and our keyboard or mouse entries. Makes sense?

Why do we care about this? Data files are stored on our computer so that we can retrieve them in the future. Maybe we need to update them, as in investment portfolio tracking, or send another copy to someone as in a resume. The question then becomes how do we find them again. My personal computer has over 105,000 files on it! Now most are program files but about 900 of them are data files. How would I ever find anything?

The trick is to subdivide them into categories I can understand, and name the categories with names that explain the files within it. These categories used to be called subdirectories (and still are by some people) but more recently have been called folders by Microsoft. Microsoft, in trying to label stuff with familiar labels, would liken your computer to a file cabinet having several drawers. Each drawer has many Pendaflex hanging file folders, and each Pendaflex file folder has several manila file folders in it. Each manila file folder can have several pieces of paper in it. Start to see the analogy?

If the computer is like the file cabinet, then each drawer is like a disk drive, either a hard drive or a floppy or a CD-ROM drive. And in each drawer, Pendaflex hanging file folders create major categories, or directories; and within each Pendaflex file folder are many manila file folders, each holding several pieces of paper.

The separate pieces of paper are like separate files. The manila file folder holding the pieces of paper define a sub-category, or a subdirectory. Hence Microsoft calls the subdirectories “folders”. Now the Pendaflex file folders are just larger categories, or directories, or “folders”. The Pendaflex hanging file folders are in a drawer. If you take out a drawer and put in a different one, it’s like taking a CD-ROM disk out and putting in a different one. A disk drive is like a file cabinet drawer! Voila!

Unlike normal file cabinets, your computer can have folders within folders within folders within folders . . .ad infinitum almost. This actually works pretty well. You can subdivide a category (folder) till the cows come home. If you do it right by naming your folders with self-explanatory names, you can actually find that letter to Aunt Sally very quickly. It will be in a folder called “Aunt Sally”, which is in turn in a folder called “casual letters”, which is in a folder called “letters”, which is in a folder called by your first name, which is in a folder called “my documents”, which is on your C: drive (for example).

My 900 or so files are split up into about 160 folders so the average number of files per folder is only 5.6. That makes the specific letter to Aunt Sally easy to find. Once I look in the right folder, I only have to look at about 5 or 6 files, and the file name can easily tell me which one I want, or the file date can also.

So how does one create all these folders? How does one move files from one folder to another? How does one delete files no longer needed? Use Windows Explorer (not Internet Explorer) for PCs. (MACs I am not familiar with.) But how to use Windows Explorer is best left to your computer manual. Suffice it to say, by using Windows Explorer one can set up folders, make new ones, change the names of old ones, copy files from one folder to another, delete files, and move files, and more. It’s a great tool, one I find indispensable.

Hint: In the newer Windows operating systems, Windows Explorer is started by right clicking the start button, then left clicking the word explore on the little pop-up menu. But be careful in there. Read a computer manual about explorer before jumping in. It’s a fantastic tool but if used without care you can delete files your computer needs to operate. But it is the only tool you can use to set up a “folder system” and make your files so much easier to find.