Acids and bases have a wide variety of uses in both our everyday home lives and in chemistry and industry. The reason is twofold. First, since they are on the polar ends of the pH scale (the scale that measures the concentration of Hydrogen molecules) they are highly reactive and corrosive. Secondly, their type of bonding, ionic, is very useful in chemistry to form other chemicals and help drive reactions.
In the home we get the most use out of acids and bases when we cook and clean. Boric acid is a weak acid used as antiseptic and cleanser. Sodium hypochlorite gets our whites whiter and is better know as bleach. Acids and bases help make soaps and unclog pipes. Perhaps the most used home acids are acetic acid and citric acid. We know these better as vinegar and lemon juice.
Acids and bases help in many different forms of industry. For example, nitric acids help make TNT (tri-nitro toluene). Acids can also be used to clean metal and tiles. Bases have many uses as well. Sodium Bicarbonate (baking soda) is used as a buffer to either bring the pH of water up or to protect its pH in the environmental field. Strontium hydroxide is used to refine sugar by bonding to it to make strontium saccharate so that impurities can be washed out.
With their proclivity to ionize, acids and bases are used heavily in an array of chemistry fields. Chemists use them to obtain elemental forms of atoms, produce gases and create different styles of salts. However, there are uses outside of this. For example, calcium hydroxide (Ca2OH) can be used to detect carbon dioxide in the air through ionic exchange.
Acids and bases are key in elements of biology, especially fatty acids and amino acids. These compounds form the basis of life. Amino acids make nucleotides and proteins that form DNA and other important molecules. Fatty acid changes form cell walls in plants and help make biological processes like cellular digestion.