Penicillin

Penicillin is a type of antibiotic that can be used to treat bacterial infections. Really important - antibiotics can only be used to treat bacterial infections. Penicillin was first discovered in 1928 by a scientist called Alexander Fleming. He noticed that bacteria he was trying to grow would not grow near a certain type of mould fungus. After lots of experimentation he discovered that the mould produced a substance that killed the bacteria. He called this substance penicillin and was able to purify it and use it to treat bacterial infections in people. The drug has gone on to save millions of lives.