Cyst is a closed sac that may contain air, fluid, or semi‑solid material. A collection of pus is called an abscess, which is not a cyst. Surgical removal of the cyst may be necessary, depending on its type and location.
A cyst is a closed sac, having a distinct envelope and division compared with the nearby tissue. Hence, it is a cluster of cells that has grouped together to form a sac (like the manner in which water molecules group together to form a bubble); however, the distinguishing aspect of a cyst is that the cells forming the "shell" of such a sac are distinctly abnormal (in both appearance and behaviour) when compared with all surrounding cells for that given location. A cyst may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, a cyst may resolve on its own. When a cyst fails to resolve, it may need to be removed surgically, but that would depend upon its type and location.
Ganglion cyst ― Asymptomatic lumps that occur suddenly between joints. If the diagnosis of ganglion cyst is confirmed, the problem may be solved by pressing the nodule hard to burst the cyst inside.
Mucocele ― It appears as a soft bump on the lips without any symptoms.
