The biceps brachii muscle has two heads, as shown in the photo.
They are called long head and short head respectively.
The long head attaches to the supraglenoid tuberosity of the scapular, which is the rough side of the radial tuberosity and the biceps brachii tendon.
The short head attaches to the rough side of the radial tuberosity at the coracoid process of the scapular.
Although the origin and insertion of the long and short head are different, they do much the same thing.
The main functions are lower arm flexion (palms facing up) and supination at the elbow joint, and arm flexion at the shoulder joint.
These are just the most important functions of the biceps brachii. The biceps brachii does many other things.
The biceps brachii muscle, with its two origins, is complex because it works across three joints: the shoulder, elbow, and proximal radioulnar joint (PRUJ).
In addition to,
The biceps brachii assist in the external rotation of the upper arm.
Biceps are strongly externalrotation with the forearm slightly flexed at the elbow joint.
The long head of the biceps works when lifting heavy objects, helping to position the humeral head in the joint and glenoid.
The short head of the biceps brachii assist in horizontal adduction.