Introduction to the "standard model"

The standard model is the theory that all matter is made up of a fairly small set of "fundamental" particles that can be grouped into "quarks", "leptons" and "bosons".

This theory was put forward in the 1960's but is still very much accepted even now, in 2015.

These particles include:
(a) the QUARKS (particles that combine to form protons and neutrons),
(b) the LEPTONS (that include electrons and neutrinos)
and (c) the BOSONS force-carrying particles (e.g. the gluons that hold the quarks together in protons & neutrons).

All bosons are "gauge" bosons (i.e. have "spin"), except for one "scalar" boson (no spin), which is the famous Higg's boson.

Quarks and leptons are collectively called fermions.

There are also anti-matter versions of all of these although there are relatively very few of them around. 

The Standard Model of fundamental (or "elementary") particles. 

The image above shows the fundamental fermions and bosons.
Please note: the masses of particles are re-evaluated from time to time.
The latest consensus can be viewed at:

Image by MissMJ, Fermi Lab Particle Data Group (via Wikimedia Commons)