Hygiene is more than just being clean. It is defined as the many practices that help people become and stay healthy. Practising good personal hygiene is essential for two reasons. First, it helps prevent people from catching and spreading illness and disease. Second, it helps people feel good about themselves and their bodies. Cleanliness is an important issue; poor hygiene is seen as unacceptable and unhealthy.

Social aspects can be affected, as many people would rather alienate themselves from someone who has bad personal hygiene than to tell them how they could improve. Bullies may use bad personal hygiene as a way of abusing their victims, using social embarrassment as a weapon.

Poor personal hygiene can have significant implications on the success of job applications or the chance of promotion; No organisation wants to be represented by someone who does not appear to be able to look after themselves.

Good hygiene includes thoroughly and regularly washing one's body (especially hands), washing one's hair, brushing and flossing teeth, and caring for gums. These grooming habits will reduce the threat of bacteria that constantly reside on the body. While a certain amount of bacteria are harmless, and even beneficial, to the body, a build-up of bacteria can harm a person's health.

As children grow older, their bodies go through a number of changes. While good hygiene is important for everyone at any age, it can require greater care at the onset of puberty. When puberty arrives (usually between the ages of ten and sixteen), it means the body is becoming sexually mature. Hormones, certain chemicals made by one's body, produce both physical and emotional changes. It is the physical changes that require greater attention when it comes to hygiene. For a young girl or boy, this means taking more time and care cleaning one's body, especially the sexual organs, dealing with acne, bad breath, and a stronger body odor, as well as doing more to prevent cavities and gum disease.