Section 7
##### Simple Programming
Even though the HP-41C has many powerful functions, you may wish to perform operations that are not already contained in the calculator. If you have read through the introduction to this handbook, you have already seen how you can increase the capability of the HP-41C greatly by writing your own programs.
Once these programs are stored into the calculator’s memory, they can be executed exactly like any of the standard HP-41C functions.
The HP-41C even allows you to define the arrangement of the keyboard. You can completely customize the calculator by writing your own specialized functions and assigning them to the keyboard locations you specify.
After most of the explanations and examples in this part of the handbook, you will find problems to work that let you practice programming the HP-41C. These problems are not essential to your basic understanding of the calculator, and they can be skipped if you like. But we urge you to work them. Each problem has been designed to increase your proficiency in programming and use of the HP-41C.
If you are familiar with other Hewlett-Packard handheld calculators, you still may wish to work through part II of this handbook. The HP-41C has many new capabilities that you can take advantage of in your programs. Programming the HP-41C is simple, just like on all other HP handheld calculators.
Note that in programming, there are usually several ways that a problem can be solved. So after you complete this handbook, you may find that you will be able to solve many of the problems faster, or in fewer instructions, than we have shown in our illustrations.
Now let’s begin programming!
###### What Is a Program?
A program is little more than a series of keystrokes that you would press to solve a problem manually. Except that when you program, the calculator remembers the keystrokes as you enter them, then executes all of the specified keystrokes whenever you wish. Because of the special capabilities of the HP-41C, programs that you write can be treated just like any other function on the calculator.
###### Creating a Program
If you read the introduction of this handbook, you created, loaded, and ran a program that calculated the heat loss from a cylindrical water heater. Now let’s create, load, and run another program to show you how to use some of the other features of the HP-41C.
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