The gingiva or gums, consists of the mucosal tissue that lies over the mandible

Mandible

The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...

 and maxilla

Maxilla

The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...

 inside the mouth

Mouth

The mouth is the first portion of the alimentary canal that receives food andsaliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth....

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Gingiva are part of the soft tissue

Soft tissue

In anatomy, the term soft tissue refers to tissues that connect, support, or surround other structures and organs of the body, not being bone. Soft tissue includes tendons, ligaments, fascia, skin, fibrous tissues, fat, and synovial membranes , and muscles, nerves and blood vessels .It is sometimes...

 lining of the mouth. They surround the teeth and provide a seal around them. Compared with the soft tissue linings of the lips and cheeks, most of the gingiva are tightly bound to the underlying bone which helps resist the friction of food passing over them.