Thermodynamics:

Thermodynamics:

The word thermodynamics is derived from a latin word "therme" and "dynamics". Where 

thermo = heat 

Dynamics = motion/force

It is a branch of physics which deals with the study of heat, temperature and it's motion and work.

Thermodynamics is the science of energy transfer and the effect of transfer on the physical properties of the substance. It is based on the observation of common experiences.

Thermodynamics is classified into two types

1. Classical thermodynamics 

2. Statistical thermodynamics 

Classical thermodynamics:

In classical thermodynamics we deal with macroscopic nature of system.

Meaning: 

we consider that the properties of a system like density, pressure, temperature, internal energy are same at each point within the system.

The overall behavior of the system is taken into consideration like average temperature, average pressure.

Statistical thermodynamics:

In statistical thermodynamics we deal with microscopic nature of system.

Meaning:

We consider the properties of a system like density, pressure, temperature, internal energy at a particular point within the system.

This type of study is conducted in low densities, i.e very few molecules are taken into consideration and experiment is conducted on those molecules only. 

It is the behavior of the the molecule at a particular point of the system.