There are about 20 amino acids which make up the bio-proteins. Out of these 10 amino acids (non-essential) are synthesised by our bodies and rest are essential in the diet (essential amino acids) and supplied to our bodies by food which we take becausethey cannot be synthesised in our body.
e.g. Essential amino acid - Valine and Leucine
Non-essential amino acid - Glycine and Alanine