I realize that last week I used the term "evangelical" a lot, and have named this feature "Fundie Friday," but I think there's a lot of misinformation and misunderstanding regarding those two terms, and I'd like to take a bit of time today to briefly (briefly) define the two terms, and discuss the differences. Many people use the terms interchangeably (even those who describe themselves by them), but each term has a specific historical genesis, and it's worthwhile to examine that.
First, since it's the easy one, let's do evangelical. The word comes from two Greek words that put together mean "good message" or "good news" -- this, then, is a sort of Greek translation for "Gospel." Put more broadly, the term refers to the Christian concept of the Great Commission, i.e. to spread the faith to all people, giving God's word to all.
It's important to note in today's religious environment that this is actually a pretty strange trait for a religion to have. Not all religions evangelize; Judaism, for instance, specifically teaches that its members are not to spread the faith unless they are specifically sought out by individuals who actually want to join, and has certain discouraging tactics. And there are plenty of religions from the era in which Christianity got its start that were "mystery religions," i.e. religions in which knowledge of the inner sancta was only granted upon successive feats of loyalty and devotion to the faith. Arguably, Scientology is such a belief today.
"Evangelical," then, is a term that applies to all Christians today, absent a few minor splinter groups that follow a more restrictive path to knowledge. There is a certain stigma to the term nowadays, given that conservative elements of the faith muddy it with their own agenda, but even very liberal denominations like the United Church of Christ or the Episcopals would consider themselves evangelical about their faith.
What, then, is Fundamentalism? While "evangelical" has a historical basis in the very earliest days of Christianity, "fudamentalism" is much more recent. In fact, it's not quite a hundred years old. The term refers originally to a series of articles published in volumes called The Fundamentals in which the authors, Lyman Stewart of Biola University and his brother Milton, attempted to summarize the root beliefs of Christian doctrine. (The link above links to an online copy of the original texts.)
You see, around this time a new academic field of textual criticism was coming into vogue. Textual criticism is a method allowing historians and students of literature to analyze literary works (such as, say, The Odyssey as historical works, that is, by attempting to analyze which parts of these stories were true and which were not-true through analyzing earlier works, historical evidence, etc. Applying this method to the Bible (in particular, the Pentateuch, i.e. the first five books of the Old Testament) yielded the Documentary Hypothesis, in which it became clear that the Pentateuch was not written by Moses himself as was taken as sacrosanct, but had four authors who contradicted each other and whose works were then redacted by a fifth. (When applied to biblical studies this technique is known as "higher criticism.")
Another target of The Fundamentals was the theory of evolution, which was around that time coming back into vogue as the Modern Synthesis reconciling Darwin and Mendel was being established. William Jennings Bryan himself preached from these books, and the idea of "biblical literalism" as we speak of it today is derived largely from them.
Over time, followers of these books became known as "Fundamentalists," as opposed to the "mainline" churches like the Episcopals that (for the most part) did not reject the teachings of modern science about the history of their faith. Fundamentalism grew out of fertile soil in the United States for a variety of reasons, but the most prominent was a long history of rejection of religious authority from afar (most religions in America preferred their religious authorities close by, not in, say, Rome) and of rejection of education and modern teaching. (This is a whole other topic which I'll deal with another time.)
So we can see that while "evangelical" is a term that refers to a simple spreading of faith, whatever the method or ideals, "fundamentalist" refers to a specific rejection of modern science and philosophy, and has a specifically anti-intellectual bent. This is why the term is used to denigrate other highly authoritarian/hidebound movements with terms like "fundamentalist Islam." Personally, I find myself gritting my teeth whenever I hear such terms, as making the explicit connection between a specific historical movement between conservative elements of the two faiths assumes a kind of one-to-one analogy that is simply not the case. Conservative Islamic groups don't behave culturally or ideologically like conservative Christian groups, and tarring both with the same brush is just asking for misunderstandings.
(For that matter, many of those who are most vituperative of "fundamentalist Islam" come from the most reactionary of Christians. Again, there are lots of historical reasons for this, and again, it's not something I'm going to get into right now.)
Now, in practice I'm basically using the two terms interchangeably, as many modern-day fundamentalists avoid the term and call themselves evangelicals. But it's important to keep the difference in mind when understanding what it is that this feature is about -- I don't have the goal of necessarily criticizing all religion, or even all of Christianity (although I am an atheist), but rather in criticizing specifcally those reactionary movements that exist only to reject modern scientific and social advance. That a person believes in God and wants to share that belief with others is perfectly fine, assuming that they are reasonable in how they act on that, but a rejection of reality that forms the basis of fundamentalism is a much different and more dangerous thing. And much more entertaining, as we'll see as I keep putting up these posts.