What is a chess opening?

Chess opening is a term that refers to the initial moves which lay the foundation for a chess game.
There are numerous ways of playing the opening phase of a chess game. By the 16th century chess players had already realized that certain opening moves proved more beneficial than others. They had started giving specific names to specific openings and had made the first steps towards the development of opening theory.
With the development of modern chess, opening theory has become more and more significant. Certain chess openings have been analyzed for almost a hundred years now, making them become more or less standard. These openings are known as book openings.
Opening theory is constantly evolving. Every now and then, strong chess players manage to find new moves in well-known positions that change the evaluation of a certain book opening. Such moves are known as theoretical novelties.
It has to be said that the opening theory has undergone truly revolutionary changes in the last 20 years. The development of the modern chess computers was the prerequisite for the invention of the chess opening databases, which have accelerated the flow of chess information and assimilation of chess knowledge.
Nowadays, theoretical novelties are common occurrence and their number and frequency are constantly increasing. Following recent trends in opening theory is a must for any chess professional. Most of them have a “Second”; usually a strong Grandmaster who analyzes certain opening lines, discovers new ideas, and documents his findings.
Before getting to the point where a player starts analyzing complicated variations and finds theoretical novelties, he has to be familiar with the basic principles of chess openings.
In other words, you have to learn how to walk before you can run.
Over the next few articles I will be discussing some Popular Chess Openings and how to play them.