Chris's Wiki :: blog/tech/AbstractionsHideUnderlyingDetails
Very broadly, there are two conflicting views of abstractions in computing. One camp says that abstractions simplify the underlying complexity but people still should know about what is behind the curtain, because all abstractions are leaky. The other camp says that abstractions should hide the underlying complexity entirely and do their best not to leak the details through, and that people using the abstraction should not need to know those underlying details. I don't particularly have a side, but I do have a pragmatic view, which is that many people using abstractions don't know the underlying details.
People can debate back and forth about whether people should know the underlying details and whether they are incorrect to not know them, but the well established pragmatic reality is that a lot of people writing a lot of code and building a lot of systems don't know more than a few of the details behind the abstractions that they use. For example, I believe that a lot of people in web development don't know that host and domain names can often have a dot at the end. And people who have opinions about programming probably have a favorite list of leaky abstractions that people don't know as much about as they should.
(One area a lot of programming abstractions 'leak' is around performance issues. For example, the (C)Python interpreter is often much faster if you make things local variables inside a function than if you use global variables because of things inside the abstraction it presents to you.)
