There are bacteria that are essential to our life, such as those involved in the digestion process. There are also opportunistic bacteria that are not always dangerous to us. There are also pathogenic bacteria that can cause disease and malfunction of organ systems. They live mainly in the digestive system: mouth, esophagus, stomach, intestines. They can also live in the urinary tract. But most of them can be found on the skin. Therefore, you need to remember the rules of hygiene.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.