Mould is a type of fungus that grows in damp and warm environments. It develops in the form of small colonies visible as spots or films on surfaces such as walls, food, wood and textiles, among others. Moulds feed on organic materials and moisture, and their growth is favoured by suitable environmental conditions.

Moulds can have various colours, including green, black, white, orange and grey, depending on the type of mould. Some moulds are harmless, while others can be harmful to human health, particularly if people inhale or come into contact with them. Some people may develop allergic reactions or respiratory problems in the presence of harmful moulds.

It is important to take steps to prevent the growth of mould inside homes, such as maintaining proper ventilation, controlling humidity and repairing any water leaks. If mould is present, it is essential to remove it properly, as its growth can damage surfaces and adversely affect indoor air quality.