You get a tank of hydrogen, and you heat it up until it ionizes. Protons aren’t exactly exotic.
Most of the guys answering this question are way too smart to be useful for we polloi. Here’s the simplified version from the Chief [del]Pedant[/del] Simpleton.
The LHC accelerates hadrons (in particular, protons) to high speeds so that when they smash the high energies break apart stuff into its teeniest components. Those teeny components can then be observed with detection mechanisms to see how they interact.
Remember the Greeks? They wanted to know what the most indivisible item was that was the building block for everything else. The atom.
Later, what had come to be called “the atom” turned out to have even smaller pieces and those teeniest pieces were so teeny it didn’t even make sense to assign them a category of “stuff” or “energy.” In fact, it turned out it was better to come up with a standard model that just called the teeniest things “quanta,” meaning the most indivisible amount of interaction with anything else.
As particle accelerators got better at identifying the types of basic interactions, the standard model (1960’s now) of interactions came up with about 16 kinds of basic interactions; every interaction is identified with/carried by/associated with a “fundamental particle.” (But note that it’s a bit fast and loose to use a term like “particle” which is stolen from the macro world. It’s a bit better to think of these teeniest things as the smallest quanta of interaction or teeny regional behaviour.) No one knows what (or even whether) they actually “are.” Essentially they are point interactions which form a substrate for mathematical modeling of “fields” (fields are descriptions of the behaviour of regions of spacetime).
In the standard model, 12 of the 16 particles are fermions (further divided into quarks and leptons). Fermions have half-integer spin and a resulting characteristic is that in their “quantum” of spacetime, no other fermion can also occupy that (teeniest) region of spacetime. Pauli described this as an exclusion principle. Therefore you can think of fermions as the teeniest thing that takes up space–they are what the Greeks thought of as “atoms” even though that term was subsequently applied to what is now a different concept.
OK; fermions exhibit certain behaviours or interactions, and in the standard model every behaviour is associated with a “particle” (again, not a very good term, but basically an indivisible quantum of behaviour). If you think of fermions as “matter” particles" then the standard model models interactions of these matter particles though the use of four force-carrying particles called bosons (bosons have integer spin, and therefore don’t have to obey the exclusion principle, so they can exist in the same “point” as fermions). A photon is a boson, for example, and is used in the standard model as the “force carrier” for the electromagnetic force. In the standard model an electromagnetic field exists because photons “carry” the force through spacetime. In simple terms, think of the photon as the teeniest possible quantum (regional behaviour) of light moving from point A to point B. Because it’s a “force” when it arrives at point B something will happen to a fermion at point B that is influenceable by the electromagnetic force.
In summary, the standard model provides 16 particles that serve as teeniest descriptions for why there is stuff and why stuff interacts. The history of particle accelerators is essentially composed of why that standard model thinks those are the teeniest quanta, and it’s a very cool history with some fairly cool predictions that were correct until the whole table of current elementary particles got filled in.
But it’s missing something. It doesn’t explain why some particles (photons, and gluons too, I guess, although gluons carry the “strong” force and the strong force is confined to a very teeny region so gluons don’t fly around like photons do) always travel at constant speed (c, in a “vacuum”) while others accelerate and decelerate and never attain a speed of c (relative to another particle). The quality that causes particles to travel at less than c in a vacuum is “mass” and so far “mass” remains totally unexplained. That is to say, there has never been any sort of direct (or indirect) evidence in particle accelerator detector analysis for a force-carrying particle for “mass.”
If you think about it, that’s a huge deal. Every elementary particle in the standard model (except photons and gluons) has this weird quality where even though there is nothing around it except “space” it cannot be accelerated to c.
To solve this dilemma, the particle physics world reneged (still in the 60s, here) on their earlier proud and hasty dismissal of the idea that the “vacuum” of space was actually filled with an “aether” --i.e. a “something” beyond just the absence of matter and energy. (I am exaggerating here, but trust me, scientists love to say the other guy was completely wrong and then substitute their own clarifications which are, in effect, simply refinements of the same underlying notion.) Anyway, back in the 60s Higgs and others proposed a mechanism by which the two force-carrying bosons in the standard model which do have mass (the W and Z particles) could acquire it: Maybe there exists a uniform “background field” (background meaning it is smoothly distributed through all of space ((an “aether”!!!)) which gives rise to mass for W and Z bosons. Maybe “spacetime” is not just a totally neutral, smooth “fluid” of some sort. Maybe it’s buzzing like crazy with ittybitty fluctuations that break an otherwise perfectly symmetrical/stable smoothness. When that happens, according to this modeling of how things are, fermions and the W and Z particles acquire mass but–most importantly here–a new “particle” is left over from the components which comprised the original symmetry. (Remember that one way to look at all these models is to recognize that they are basically mathematical calculations which all need to sort of even out; the triumph of modern particle physics math is that the math frequently predicts the existence of a “particle” which lo and behold we then detect with the particle accelerator).
Anyway, that left-over particle from the Higgs mechanism is…ta daaa: the Higgs boson. (I believe the Higgs boson would be the first elementary particle associated with carrying a scalar fields, but this is well beyond my ken).
The Higgs boson’s mass is unknown, but proposed to be 100 (or more) times the mass of a proton. So (as referenced above) you need the LHC to get those kind of energies.
I snerked 
Thanks for that!
yeah Chief, that was soooo much simpler.
I believe any actual scientist would recognize it as a post by, and for, a simpleton. 
Here’s a new shot a summary:
For 50 years, the standard model has been accurately describing and predicting how the stuff of the universe works. Discovery of the Higgs boson by the LHC will lend credence to the model because it is the last predicted particle needed to flesh out the basic model.
Yeah, we get it. the Higgs is the missing link and it proves evolution and disproves creation.
Most of that link is beyond my ken but this part stood out:
I’m sure they know what they are about but really? Is this some super, earth splitting proton beam or something?
IIRC a Russian scientist got his head in the way of a proton beam. Granted it was a lot lower power than the LHC and it messed him up but he lived. Seems the LHC would do fine with a dozen scientists heads in the way to stop it. 750 tons of concrete though? They think something less, say a mere 100 tons, would be pushed out of the way? Better yet why not just point it into the earth? Dig a hole and shoot the beam down it. Would cost less I’d think than all that stuff.
I’m sure this question will (further) highlight my ignorance, but I’ll ask anyway. Does any of LHC plan include addressing the dark energy problem? If I recall, this problem has to be solved before we can come up with a “Theory of Everything”.
SShhhhhhh!
thats a black opps project
And how do you propose that we aim the beam down the hole? Put the whole device on giant jacks and tilt it sideways?
The problem is redirecting the beam. The LHC is so big because you need a very gentle curve to bend the fast-moving particles around in a circle. If you’re going to shoot the beam into the earth, you’d need a similar huge curve with lots of expensive magnets to bend it down. It’s much cheaper to let the particles shoot straight off along a tangent into a big damper with a heat sink.
Actually, I don’t think the total energy of the beam is as high as this makes it sound.
My educated WAG is that they are worried about the amount of energy that gets dumped SCATTERING BACKWARDS into the accelerator. Given its precision, and expense, you want to make sure ALL that gets dumped stays DUMPED so to speak. It would be like having a billion dollar car. Getting some really fancy and expensive tires are worth the insurance that nothing bad happens.
And the bolded part in combo with your user name is just too cute.
Actually, it is.
The web page Krinthis linked to reported a total beam energy of 350 MJ (in a beam about 2mm wide). This is the energy-equivalent of about 80 pounds of TNT. It’s going to vaporize a lot of the carbon in the absorber and create a serious blast wave that needs to be contained and/or kept well away from the rest of the LHC while it dissipates, thus the steel casing and concrete. It also will heat up the rest of the carbon, thus the need for water cooling.
OK, just to sum up here and clarify: if the Higgs boson exists and if its mass is actually what it is predicted to be, then the LHC should be able to spot it. If it’s the size that we think it is, we don’t need to build a bigger accelerator, right?
I stand corrected.
I thought the LHC was some 300 feet underground. So just shoot it into the earth right in front of it. I may be wrong how deeply it is buried…think I saw that number cited somewhere. Still, even if it is 50 feet underground just shoot it into the earth.
I’m sure this is not a stupid question, but I fear I may be too ignorant to understand the answer 
If I understand you correctly, when you collide two massless particles, you get a new massive particle + a Higgs boson which also has mass. So the “particle” that actually gives mass to stuff can’t be the Higgs boson, since it’s way more massive than other massive particles, right? Where did all that mass come from then?
Thank you, I thought it would be something simple like that.
Note that protons are not massless. The nearest thing we have to a “massless particle” is a photon (note the second letter: h, not r) which is sort of but not quite a particle.
From the pre-collision energy (bearing in mind the mass equivalence of energy, according to E = MC[sup]2[/sup]).
Correct - around 76 pounds, according to my sources.
I did some Googling and found my ignorance fought thusly: 350MJ is also the equivalent of around 2.83 gallons of gasoline, which has an energy density per unit mass about 10 times that of TNT.
Whoda thunk it?