Obviously with any scientific discovery of this magnitude, there's a lot of room to ensure absolute certainty and so pending confirmation, we can't be completely sure that the Higgs has been discovered. But under the current announcement, the certainty is at 5 Sigma standard deviation (approximately one chance in two million that there is a mistake), so it looks like the Higgs Boson has in fact been discovered.
Normally, I'd wait until the end of the month for a science wrap-up, but a discovery like this deserves its own post. Seriously, this is awesome.
What is a Boson?
Simply put, it's an elementary particle.
Everything is made of matter. And matter is made of molecules, which are made of atoms, which are made of subatomic particles, which are in turn made of elementary particles. A boson is one type of elementary particle, and the Higgs Boson is one type of boson.
The other types are the photon, gluon, Z boson, and W boson. The photon is responsible for electromagnetism, the gluon handles the strong force, and the W and Z both handle the weak force. These make up three of the four fundamental forces of nature, the fourth being gravity (though it has been argued that gravity is a projection of the interactions between the other three forces).
Since gravity is essentially an acceleration caused by objects' masses, and since none of the other bosons or other elementary particles seems to dictate mass, the question of where mass comes from has been one that has plagued physicists for some time. This is where the Higgs Boson comes in.
What is the Higgs Boson?
Essentially it's the particle that gives us mass, which is a measurement of how much stuff is in something. (A gram, for instance, measures mass. Interestingly, an ounce/pound does not; that measures force, which is mass times acceleration; in the case of weight, this acceleration is due to gravity. In the standard system, we don't have a very good unit of mass. This is one of the very few times in which the metric system is better.)
The Higgs Boson was first proposed in 1964 by Peter Higgs and five others. It was proposed to answer the question "where does mass come from?" since none of the other elementary particles could answer this question. Some elementary particles in fact have mass, but this is not required for any equations to work; in other words, there must be some reason they have mass, and it's not to fulfill their functions. The Higgs Boson solves this by positing a Higgs Field that imparts particles with mass.
How does the Higgs Boson work?
Well, assuming it actually exists, and again, this is still tentatively announced, (though seriously, at a certainty of 5 Sigma, we are pretty safe in this assumption) the Higgs Boson creates a field, just like other bosons, which acts as a mass-imparting-mechanism. How it works is complicated, but a simple explanation can be drawn from a sporting event.
Imagine that a large group of fans is outside the ESPY awards ceremony, and for whatever reason, are unfettered in their ability to interact with the various athletes coming through. Before any athletes arrive (assuming this is an open space, like, say, a field), the people are relatively well-distributed.
Suddenly, LeBron James and Tim Tebow arrive, simultaneously, at opposite sides of the field. Immediately, fans are drawn toward them, crowding around, and slowing down James and Tebow, who now have much more "mass" of fans. When Kris Humphries arrives later, he gathers a small crowd, but not large enough to significantly slow him down. He has much less mass.
Basically, some particles, like the W and Z, have large mass, because they are the James and Tebow of the Higgs field. As they go through the field accompanying the Higgs Boson, they "pick up" mass. Meanwhile, other particles, such as the Gluon, are reviled by the elementary particle world because of their relationship with Kim Kardashian, and therefore do not attract any mass.
Is this discovery a good thing?
So that's an interesting question. It's good, in that it will bring us closer to proving Peter Higgs right, and giving us a more complete understanding of particle physics. And it's good in that the CERN, who discovered this, was focusing on this goal first and foremost. However, interestingly, it's not all good. Finding that what we expected is true is a little boring. Had we instead never found the Higgs Boson, we'd have to do all kinds of crazy things to find a different answer to the mass question.
However, I'm in the camp that knowledge is good, and therefore I am very excited about this discovery. Sure, this will take away one question, but there are so many more questions, I'm sure we won't run out anytime soon.