Small blackish warts on the hand and foot are usually caused by a common viral infection called Human papillomavirus infection, and they are generally harmless but can cause irritation. Many warts go away on their own, but if you want treatment, over-the-counter options like salicylic acid solutions or wart-removal patches can help gradually remove them when used regularly, while protecting the surrounding skin. It is important not to pick or cut the warts, as this can spread the infection. If they are painful, increasing in size, spreading, or not improving after a few weeks, a doctor can treat them more effectively with methods like freezing (cryotherapy), cautery, or minor procedures. Keeping the area clean and dry and avoiding sharing personal items can help prevent the spread.