programming-for-dummies

Chapter 5: Managing Large
Projects with Software Engineering
In This Chapter
Choosing your software engineering method
Using CASE to automate software engineering
The pluses and minuses of software engineering
Writing a small program is easy. You just type your program in an editor
and shove your source code through a compiler. If you find any problems,
dig through the source code, fix the problem, and recompile the whole
thing all over again. No matter how many bugs pop up in your program,
chances are good your program is small enough so you can hunt any bugs
and wipe them out without much trouble.
What happens if you need to write a massive program to control the flight of a
satellite in orbit or an automatic safety system for monitoring a nuclear plant?
Unlike simple programs that can consist of a few hundred lines of code, massive
programming projects can contain millions of lines of code. How can you
create such a large program, let alone debug, test, and maintain it?
That’s where software engineering comes into play. Just as it’s much easier
to pitch a pup tent by yourself than it is to construct a skyscraper on your
own, it’s also easier to write a simple program by yourself, but nearly impossible
to write a million-line program all by yourself.
When you have to write a huge program, you probably can’t do it alone, so
you need to work with a team of programmers and coordinate your efforts.
Even before you write a single line of code, you need a plan for creating the
program from the start. Just as no one starts welding I-beams together to
build a skyscraper without making plans first, no one tackles a massive software
project without a lot of planning ahead of time.
Software engineering is about creating guidelines to help people consistently
write reliable programs within a reasonable amount of time. The fact that governments
and Fortune 500 companies routinely start massive software projects
with no plans (and often abandon them after never getting them to work
despite spending millions of dollars) is proof that software engineering is a
nice term that often gets completely ignored in the real world.