”X-ray is the first choice for bone tumor diagnosis, which can reveal the following symptoms: 1) the location of lesion 2) the type of bone destruction 3) the integrity of bone cortex 4) the edge of lesion 5) the presence of sclerotic border 6) the presence of residual bone within the lesion 7) the calcification of tumor cartilage 8) the formation of tumor bone 9) the presence of periosteal reaction and its type 10) the change of soft tissue around the lesion area. The presence of periosteal reaction and its type 10. soft tissue changes around the lesion area and other signs The clinician can determine whether the patient belongs to tumor or non-tumor, benign or malignant, primary and secondary lesions through the above symptoms. With the development of digital technology, the quality of “X-ray plain film” has been gradually improved, and ordinary X-ray plain film has been replaced by CR and DR. Through these technologies, we can obtain more and more accurate information to arrive at an accurate diagnosis. In clinical practice, we often encounter patients who ask about the difference between “CT and X-ray plain films”, which is explained in the simplest terms: CT is good at detecting internal changes in bones, while X-ray plain films are good at detecting external changes in bones. The characteristics of the two are different, and CT and other large tests cannot yet replace the pioneering position of X-ray plain film as the “most basic test”.