The verruca (plural verrucae) is simply a wart.  Most verrucae occur on the soles of the feet but they can also grow around the toes.  The young verruca looks like a small dark puncture mark but later turns grey or brown.  It is possible for verrucae to clear up without help but they can spread easily.  More from the Royal College of Podiatry.

Sweaty Feet

You may already know that sweaty smells (including smelly feet) are caused by bacteria that enjoy warm, moist conditions.  Feet have more sweat glands than anywhere else because the moisture is needed to keep the flesh supple; so feet will continue to sweat even when they are not hot!  Rigorous hygiene is the best prevention and cure.  Give your shoes a chance to dry out by avoiding wearing  the same shoes all day every day.  Leather shoes are naturally breathable and lace ups don't have to be such a tight fit as slip-ons so may allow better air circulation 

When walking or standing, weight is taken on the heel and ball of the foot where the skin grows thick to withstand the pressure.  The skin may  thicken anywhere where there is excessive pressure as a protective response.  Sometimes this thickening develops into an uncomfortable corn or callus.  Most calluses indicate an underlying problem such as a bony deformity or inappropriate footwear.  Some people have skin that hardens up more easily and elderly people are also prone to corns and calluses because they tend to have less fatty padding tissue.

A callus can become painful, 'like walking on stones'.  The podiatrist can remove the callus to give rapid pain relief, 'like walking on air'.  You should also expect preventive advice and treatment, for example padding to redistribute weight. 

An ingrowing toenail is one which has started to pierce the flesh of the toe.  It sounds painful, and is!  Pain like a splinter is an early sign.  An ingrowing toenail can cause bleeding and infection and the sooner it is treated, the quicker and less painful the treatment.

Causes include the way you stand (posture), the way you walk (gait) and some people's toenails just have a natural tendency to curl inwards. Perhaps the most common cause, however, is not cutting toenails properly (the risk of an ingrowing toenail is a good reason not to pick your nails.) 

Athlete's Foot is a fungal infection.  You can pick up fungus anywhere where you walk barefoot but especially communal areas such as changing rooms, showers and pool-sides.  Once a foot has been contaminated, the warm sweaty shoe or trainer creates ideal growing conditions.  Some fungi species also like it if summer sandals allow feet to dry out too much and lose their natural protective oils.

Wear flip-flops in the shower and changing rooms.  Keep your feet clean, and dry them thoroughly before putting on socks and shoes.  Don't wear the same shoes every day.  Choose socks and shoes that let your feet breathe. 

Your pharmacist may be able to recommend a treatment avoids the need to visit the podiatrist.