Theory:

The lesson "Fire: Friend and Foe" talks about the pros and cons of fire. Three components are involved while creating fire. They are fuel, oxygen, and heat. Fire is created when the three components are brought together. Examples of fuel are wood, coal, cooking gas, and petrol. Oxygen, on the other hand, is found abundantly in the air. Heat is the initial stage of the fire. For instance, fire has a lot of uses, such as to cook food, warm houses, create electricity, light lamps and candles, etc. We use fire at our homes every day. Fire had also helped the early human settle down and lead a more civilised life.
 
Fire is also a source of destruction when it goes out of control. Fire kills hundreds of lives, ruins thousands of homes and shops, and destroys vast areas of forests every year. Hence, we should always keep the fire under control. As the saying goes, fire is a good servant but a bad master.
 
While there are three components needed to create fire, there are also three ways in which we can put out fire. We can put out the fire by stop adding fuel into it. The second method involves the oxygen. When we throw a wet blanket or sack on the fire, the fire will stop as the oxygen is blocked. The third method involves the heat. Spraying or pouring water can bring the temperature down below the flashpoint. In the case of oil or electrical fire, we should use carbon dioxide extinguisher instead of water.
 
Earlier, when we didn’t have firefighters, the common people fought fire together by forming a human chain. However, we have professional people to fight and control fire. They are called the firefighters. They have various skills, such as to put off fire, rescue lives, give first aid, etc.

Though fire is pure science, people from many parts of the world still worship fire. The reason being that fire is both the source of life as well the source of destruction. If not treated with caution, fire will turn deadly. Fire can be a great friend, but, when taken lightly, it can be a dangerous enemy.