The Large Hadron Collider is pretty interesting. New subatomic particles are being discovered with its utilization. Just last Friday a new particle was discovered - "neutral Xi_b^star baryon". The new particle is made up of three quarks, and only exists for something like .00000000000000000000001 seconds.
If it only exists for an amount of time that can not really be observed, then how do we know if it even exists? Well, scientists examine the end product, and from those results they are able to determine (somewhat) what type of particle existed. The "somewhat" comes from the fact that tons of tests have to be performed, and data analyzed across a large number of experiments to get information they can use.
The ultimate goal of the Large Hadron Collider is to discover the existence of the Higgs Boson Particle. The theory is that the Higgs Boson particle is responsible for giving mass to other particles, and is the missing puzzle piece in understanding particle physics.
The Higgs Boson particle is expected to be found later this year.
I am not a scientist, obviously, so why not hear it from the source. Actual scientist working on the actual Large Hadron Collider.