Full Idea
As presently formulated, the standard model is two theories. One operates in the sector of strong interaction, and the other in the sector of the electromagnetic and weak interactions.
Gist of Idea
The standard model combines theories of strong interaction, and electromagnetic and weak interaction
Source
Brian R. Martin (Particle Physics [2011], 01)
Book Reference
Martin, Brian R.: 'Particle Physics' [One World 2011], p.16
A Reaction
The first is Quantum Chomodynamics (QCD). The second is Quantum Electrodynamics (QED). Interesting that the weak interaction is included in the latter, which (I take it) means there is an electro-weak union. Interactions are the heart of the model.