This is a common finding on a chest X-Ray.  Nodule means a spot in the lung on a chest X-Ray they look like round white spots and are less than 1 inch in size

Most nodules are benign (non cancerous) but up to 20% can be cancerous (malignant).  In case the nodule is malignant (most are not) the cancer could be coming from the lung (lung cancer) or from some other organ (metastatic)

Nodules can be single (solitary) or multiple.

It is important to know if you any symptoms such as coughing up blood, chest pain, shortness of breath, fever, night sweats or weight loss

Another useful technique is compare the X-ray or CT scan to any previous scans or X-rays of the chest

Some nodules have calcium in them (calcified) and the pattern of calcification can be used to determine the type of the nodule

Non cancerous causes of nodules include fungal infections such as coccidiomycosis (valley fever); other infections such as tuberculosis; these infections can be active or inactive.

Old infections may form a granuloma

Sometimes   a collection of normal lung cells may form a hamartoma, cysts and malformed blood vessels can also form nodules

Noncancerous lung nodules usually require no treatment. However, your doctor will probably monitor the nodule for changes using periodic imaging tests.

A CT scan is usually the first test for a suspected malignant nodule

If a lung nodule is new or has changed in size, shape or appearance, further testing  such as a CT scan, positron emission tomography (PET) scan, bronchoscopy or tissue biopsy  (to determine if it is cancerous) may be required.