Pulses.

Image source here. 

What is a pulse? It is a reflection of the heart beat, but more specifically, it is the pulsing of arteries as blood is pumped through them.  You can palpate a pulse by pressing a large artery against a bone in the body. Arteries are surrounded by thin layers of muscle that expand to allow blood to pass through it and contract to propel the blood to the next location.

Why listen to our pulse? We can get valuable information about how hard our heart is working by 'listening' to the pulse.  Try this mini exercise: next time you feel stressed, palpate your pulse. Try to describe it (rapid, quick, etc).  Then, right before you fall asleep, as you are lying in bed, palpate your pulse again. How is it different? I'm guessing your pulse will be slower and gentler before bed, compared to the race-y, fast-paced, and stressed-out heart beat that you felt earlier.

Another reason to listen to our pulse (especially in varies places of the body): if we are suffering from any type of occlusion/blockage, a particular pulse may feel weaker, diminished, or even absent! For example, people with very poor circulation may have fairly faint feeling pulses in their feet (the dorsalis pedis pulse, #9).  

We have many areas on the body where you can palpate your pulse: 

We have the temporal pulse (1, on top of our temples), the carotid pulse (2 and 3, on the front of our neck, never palpate these at the same time!), the brachial pulse (4, in the crease of our elbow), the radial pulse (5, on the wrist below the thumb), femoral pulse (6, in the crease of the leg/torso), popliteal pulse (7, on the back leg, opposite to the knee), dorsalis pedis pulse (9, on the front of the foot), and posterior tibial pulse (8, on the inside of leg, above the ankle). 

*If you are looking to find a particular pulse, leave a comment and I can describe its location in more detail than I have given above.