59. Variable names
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When people start programming in Basic, there is a tendency for them to
stick to variable names like A$, B%, FRED etc.. This has three drawbacks.
First, it is not very easy to pick out variables from keywords like FOR,
TO, PRINT etc., as everything is in capitals. Second, it is easy to
accidentally use a reserved word as part of a variable; TODAY is the
classic mistake, as it starts with TO. Third, when you return to the
program after a few days or weeks break, you will find it hard to remember
just what A$ meant. The solution is to use lower-case variables whenever
possible, and use long, meaningful variable names like "name$", "year%",
"degrees" etc.. If you are really pushed for memory space, then using the
single-letter integer variables A% to Z% can help, as can shorter variable
names such as "nd$" instead of "newdate$", but by and large you will not
need to resort to that.