The Standard Model is the quantum field theory of all known fundamental interactions except gravity. It is based on the gauge group SU(3)_C x SU(2)_L x U(1)_Y, with matter content consisting of three generations of quarks and leptons, and the Higgs doublet. Its 19 free parameters are determined by experiment. Every prediction has been confirmed, including the Higgs boson discovery in 2012.
The Standard Model of particle physics is a quantum field theory based on the gauge group SU(3)_C x SU(2)_L x U(1)_Y. SU(3)_C is the color gauge group of QCD, mediating the strong interaction via 8 gluons. SU(2)_L x U(1)_Y is the electroweak gauge group, mediating the weak and electromagnetic interactions via the W+, W-, Z, and photon. The Higgs doublet breaks the electroweak symmetry to U(1)_EM, giving mass to the W, Z, and all charged fermions.
The matter content consists of three generations of quarks and leptons. Each generation contains an up-type quark, a down-type quark, a charged lepton, and a neutrino: (u, d, e, nu_e), (c, s, mu, nu_mu), (t, b, tau, nu_tau). Left-handed fermions form SU(2)_L doublets; right-handed fermions are singlets. Quarks carry color charge (SU(3) triplets); leptons do not (SU(3) singlets). The three generations are identical in their gauge quantum numbers but differ in their Yukawa couplings (and hence masses) -- why three generations exist, and why their masses span five orders of magnitude, is unexplained.
The Standard Model has 19 free parameters (in its minimal form): 3 gauge couplings (g_s, g, g'), 6 quark masses, 3 lepton masses, 3 CKM mixing angles and 1 CP-violating phase, the Higgs vacuum expectation value v, the Higgs self-coupling lambda, and the QCD vacuum angle theta. Including neutrino masses and mixing adds 7 more (3 masses, 3 angles, 1 or 2 CP phases). All are measured experimentally; the theory does not predict their values.
The experimental success of the Standard Model is extraordinary. QED predictions agree with experiment to 12 significant figures (electron g-2). Electroweak precision measurements at LEP predicted the top quark mass before its discovery. The Higgs boson, predicted by the theory, was discovered at the LHC in 2012. QCD describes jet production, scaling violations, and the running of alpha_s with percent-level accuracy. Despite this, the Standard Model is known to be incomplete: neutrino oscillations require physics beyond the minimal model, dark matter and dark energy have no Standard Model explanation, and gravity is not included. The Standard Model is best understood as an extraordinarily successful effective field theory valid up to some energy scale, beyond which new physics must appear.