The systemic circulation is also called greater circulation.
The blood is pumped from the left ventricle of the heart into the aorta.
The aorta ascends, bends downward, forming the aortic arch, and then descends, until it bifurcates to the left and right iliac arteries.
Major aortic branches are the brachiocephalic, the common carotid, the subclavian and the common iliac arteries. From these arteries, also called elastic arteries, originate muscular arteries, arterioles and capillaries.
The capillaries are drained by venules, that come together to form veins. The veins from the head, neck and arms come together to form the superior vena cava; the veins from the lower part of the body merge into the inferior vena cava.
Superior and inferior venae cavae deliver blood to the right atrium.

Pulmonary circulation

Also called lesser circulation.
Venous blood pumped from the right ventricle passes through the pulmonary valve and into the main pulmonary artery. The main pulmonary artery bifurcates into the right and left pulmonary arteries.
From the right pulmonary artery originate two branches: inferior and superior. The inferior branch provides blood to the middle and lower lobes, while the superior branch provides blood to the upper lobe.
From the left pulmonary artery originate two branches supplying blood to the two lobes of the left lung.
The blood is oxygenated in the pulmonary capillaries and return to the left atrium via the four pulmonary veins (two right and two left).

Portal circulation