A Verruca is the common name for a wart that appears on the foot on the foot and is caused by certain types of the human papilloma virus. It appears as a pale, slightly raised area often with small black dots in the centre.
Infection is more likely to occur if your skin is moist or broken. Wet, rough surfaces - in swimming pool or gym changing areas for instance - are thought to increase your chances of picking up the virus.
Wearing flip-flops in these areas, or verruca socks while swimming will reduce the likelihood of an infection. Keeping your feet clean and dry is also a good idea.