The testicles are found in the scrotum. They are suspended by the body by the spermatic cord.
The left testicle normally hangs a little lower than the right one.
The testicles produce the male hormone testosterone. They also produce sperm cells: 75-150 million a day.
The testicles are very sensitive. Some guys love it when they are stimulated during lovemaking, others dislike it when they are touched.
When you have a sudden, terrible pain in one testicle it can be a torsion. You should seek help immediately.
Make it a habit to examine your balls monthly.

I only have one testicle and I’m ashamed of this. What’s wrong?
One testicle is bigger than the other, but both look too big. What can I do about it?
I have a short stabbing pain in my testicle after masturbating. Should I worry about this?