I had the opportunity to explain the differences of Linux and Microsoft Windows (and Microsoft the company vs. open source development)  to my mom over an e-mail. She had accidentally deleted the contents of an e-mail she was writing to my aunt in Thunderbird. She questioned that maybe someone had gained control of her Ubuntu workstation at home (tied to her DSL) and were making changes.

I explained to her (in my traditional Linux zealot way, since I mean, she’s my mom so I can kinda go off a bit and not worry about sounding so PC) that it would probably be more likely that “they” (maybe the government, or the unknown programmers that created her OS) would more likely be able to do this kind of thing through proprietary, binary-only software.. I compared open-source vs. closed source programming methods to a hypothetical auto industry. Enjoy!

Microsoft is a single company that makes and sells Windows and Office
and all of that kind of software. Their software is "closed source".
This means they don't share their software with anyone, and people can't
look at the internals of it and make it better. Microsoft software would
be kind of like a car that you buy where the hood is sealed shut, and
you have to pay them to modify the core parts of the system (I.E. you can't
modify things yourself if you want to because it's Microsoft's
"Intellectual Property"). A number of auto mechanics truly dislike the
Microsoft car because you have to jump through all sorts of hoops to be able
to fix or add things, because Microsoft blocks them from being able to get under
the hood. This is all because Microsoft wants to make more money selling
their next car, with improvements only they made. Microsoft cars also
often have a "master key" (which not many people know about) that allows
them (or anyone they give a master key to) full access. If you don't
believe that, check this out:

http://www.zdnet.com/news/ms-admits-planting-secret-password/106851

That's just one example that people found out by "hacking" proprietary
software. Who knows what else is in there that people don't know about,
since Microsoft doesn't give their blueprints to anyone.

Unlike Microsoft software (and much of the software available for
Windows), Linux and pretty much all of the other software on your
computer now is "open source software". Open source software is a
cooperative effort between expert computer programmer volunteers and
companies from around the world (like Google, IBM and Intel). Linux is
like a car that you buy where the hood isn't sealed. In fact, you get
the car's user manual, as well as the blueprints of every part of the
car like the engine and transmission. All of the information about the
car, how it's built and how it runs, is made freely available to you and
everyone else in the world. Of course, that doesn't mean that the Linux
car doesn't come with locks and a security system - to the contrary,
most people believe the Linux car has much more secure locks and
security systems than the Microsoft car. Auto mechanics like the Linux
car because they can learn exactly how it works, inside and out. They
can even make replacement seats, windows, stereos, that fit perfectly
since they have the blueprints of everything. Most people who "get it"
see this open-source mentality is a very good thing, as many independent
pairs of eyes are looking at the blueprints for flaws on a daily basis -
this encourages everyone who helps create it make it the best and most
secure possible - and if there are flaws, they will be pointed out (and
fixed) very quickly.

Hope that helps you understand that there aren't any government spooks inside your
Linux computer mom :)