There are over 200 particles that have been discovered that can be systematically classified like elements in the periodic table. All matter in the universe, from what is seen on Earth to outer space, is made up of 12 fundamental particles and their antiparticles. Each fundamental particle has a corresponding antiparticle with the same properties but opposite charge. These fundamental particles and force carriers make up the three generations of quarks and leptons that form all known matter according to the Standard Model.

2. There are now more than 200 particles being
discovered.
Just like the periodic table in chemistry, these particles
can also be classified in a systematic way.
In fact, all matter of every types: be those seen in
Earth, or outer space or those only exist in high energy
conditions, are made of various combinations of
twelve basic building blocks or fundamental particles.
Together with the basic force carriers, these particle
made up of all known matter.

4.  In addition to the above listed twelve fundamental
particles there are also twelve corresponding
antiparticles.
 They are the basic building blocks of antimatter which
made up the anti-universe.
 Antiparticles are identical to particles, except the sign
of the values change.
 For example, the electron has a charge -1, while the
antiparticle counterpart is +1, and is called positron.
Similarly, a proton is +1 while antiproton is -1.

7. From the table it is shown that for each generation
there is a pair of quarks and a pair of leptons.
There is also an increase in mass as the generation is
increased, which indicates an increase in energy for
the matter to exist in a given generation.
The first generation particles are responsible to make
all the ordinary matter.
From all the existing experimental evidence and
observations of our present universe there is a strong
indication that there is only three generations and the
list shown above is complete.

9.  This fundamental model structure is known as the
Standard Model. Notice the word Standard and it does
not mean complete. More about the Standard Model
will be discussed in the section
 The earliest classification scheme for
Unification.particles was based on their masses.
 They can be grouped into three: leptons (from the
Greek word for small), mesons (means middle in
Greek) and baryons (which means heavy in Greek).