Elementary particles are those particles which are indivisible and not made up of other particles.

Proton and neutrons       --------->    Made up of Quarks

Types of Particles

1. On the Basis of Mass:
    a. Light-mass Particles
    b. Intermediate-mass Particles
    c. Heavy-mass Particles


2. On the Basis of Charge:
    a. Positive Charge Particles
    b. Negative Charge Particles
    c. Neutral Particles


3. On the Basis of Spin:
    a. Fermians - Odd Integer multiple of 1/2
    b. Bosons: Even integer multiple of 1/2 (or simply integers, 0,1,2, etc.)


4. On the Basis of Average Life Span:
    a. Stable - Long Life
    b. Unstable - Very Short Life

Interaction Forces:
 a. Gravitational
 b. Electromagnetic
 c. Weak Nuclear Force (between leptons and hedrons)
 d. Strong Nuclear Force (between quarks)

Anti-particles: Anti-particles are particles having all properties similar except any one property w.r.to the other particle.
        eg:  

Pair Production: The phenomena of conversion of energy into matter is called pair production. When energetic photon strikes the heavy nucleus, particles and it's corresponding anti-particles are produced.