It might be worth you buying a book on the basics, or ordering one from the library.
Variables are just a more useful way to use numbers in general although they can store words (strings).
For instance
do
print "10"
loop
That will print 10 until you exit the loop.
a=1 `****** sets up variable a and gives it a value of 1
do
print a `****** prints variable a's current value
inc a,1 `****** increments variable a by 1
loop
That will count up by 1 until you exit the loop. As you can see, using a variable allows you to do things you couldn't if you simply used a number.
There is some basic help included with Db and Db Pro so best to start in there if you have no clue where to begin(the principles section in DB Pro's help is where I would recommend you start).
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