A little knowledge is a dangerous thing is a very old proverb by Alexander Pope which means that people with very less knowledge and limited experience can often mislead people. It also means that it sometimes happens that gaining some knowledge can make a person believe that they have now become experts in their field which is foolishness .There are examples where people have resulted in hurting theirselves by gaining knowledge from internet like cutting their own hair or trying some dangerous acts. So, it is advised to gain maximum knowledge before commenting, advising or performing any task.