What is a chemical bond? How is it formed?

A chemical bond is one in which atoms of different or same elements combine to become stable. There are two types of chemical bonds – electro-valent bond and co-valent bond. In an electro-valent bond, a metal donates an electron to a non-metal and forms the bond. Such bonds are very strong. A co-valent bond is formed between non-metals only. These are easy to break.