Impetigo is a contagious bacterial skin infection that primarily affects children but can occur in people of all ages. It is caused by either Staphylococcus aureus or Streptococcus pyogenes bacteria and is characterized by the presence of red sores or blisters that burst and form a honey-colored crust. Impetigo is typically a mild and superficial skin infection, but if left untreated, it can spread and lead to complications.