[Content Warning: This page is discusses many types of fluids. Feel free to skip this section if that’s not your thing.]
This is the most common thing to come out of a penis. Usually happens to anyone who owns a penis several times a day. Urine is a waste product of the biological processes of the body. It is usually released in a high pressure, high velocity stream. It is a flowing liquid in consistency and ranges from clear to deep yellow-brown in color. The exact volume varies, but it is typically a notable amount.
Semen is usually discharged during ejaculation. Semen consists of sperm and several other fluids, all mixed together. Sperm are microscopic tadpole like cells which can combine with another special type of cell in someone else’s body and cause it to turn into a baby, which is really weird when you stop to think about it so let’s not stop to think about it.
Sometimes the force of ejaculation will propel the semen at high speed some distance (up to a couple of feet) away from the penis, while other times, it won’t flow with enough energy to go even half an inch.
The consistency of semen can vary considerably. Sometimes it can be thin and watery, other times it can be thicker and closer to the consistency (though not stickiness) of syrup. Over time, even the thicker type will tend to thin out and become more runny.
Semen is usually white or yellowish white in color, although it may appear more clear when it is thinner.
The exact volume varies, but it is usually a fairly small amount, on the order of just a few milliliters.
Sometimes when aroused (although not necessarily erect), the penis will begin to produce a small amount of pre-ejaculatory fluid, also called “precum”. This is a clear, slippery, viscous fluid. It’s similar in consistency to some kinds of liquid soap and a small string of fluid will bridge the gap if you pull a drop away. Pre-ejaculatory fluid is not expelled with any force at all, and will usually remain around the opening of the urethra unless gravity or some other force acts on it. This fluid does not always appear, and when it does, it is often just a few drops. In some cases, there may be enough to use as a lubricant for stimulation purposes.
Pretty much anything else that comes out of a penis is something you should see a doctor about.