What are the three main veins in arm?

1. Median cubital vein: The median cubital vein is the most common vein used for venipuncture. It is located on the anterior surface of the forearm, between the biceps and triceps muscles.

2. Cephalic vein: The cephalic vein is located on the lateral side of the forearm. It starts at the wrist and runs up to the elbow, where it joins the brachial vein.

3. Basilic vein: The basilic vein is located on the medial side of the forearm. It starts at the wrist and runs up to the elbow, where it joins the brachial vein.