A good example of the octet rule would be chlorine, which has seven electrons in its outer shell and bonds easily. Chlorine is able to bond with elements like argon so it can attain eight electrons and fulfill the octet rule.
The octet rule can also be described as the measure of the likelihood of a chemical bond between atoms. The octet rule also states that elements lose or gain electrons to acquire an electron configuration that is the same as the closest noble gas. Atoms always try to follow the octet rule to seek out the most stable electron configuration.