Sinus is the cavity or air filled space present within bones of face. They are located in the cheeks (maxillary), forehead (frontal) and around the eyes (ethmoidal).Infection and inflammation of these cavity is called sinusitis.
According to the severity of symptom sinusitis is divided into two part:
Acute and chronic sinusitis
Both have similar signs and symptoms, but acute sinusitis is a temporary infection along with cold and flu, where as recurrent attack of acute sinusitis hamper the normal function which lead to chronic sinusitis.
•    thick, yellow discharge from the nose
•    Nasal congestion, causing difficulty in nose breathing
•    Reduction of sense of taste and smell
•    Consistent Pain, tenderness and swelling around eyes, cheeks, nose or forehead
Some other associated symptoms:
•    Ear pain, sore throat
•    Aching in your upper jaw
•    Bad breath (halitosis)
•    Fatigue
•    And some time nausea