system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is libido?

Is it a psychological need for sex? Like I am thinking about sex all the time so I have high libido? Or is it the physical hornyness? The strong need to ejaculate? Is it possible to have high libido and be impotent at the same time?
gpt
Libido, Arousal, and Erections are different.

Libido is the desire for sex and procreation. If you want sex, you have a functional libido. If you want sex a lot, and consistently, you have a strong one. This is like the "climate" of your mind.

Arousal is the mental and physical alertness that comes from stimulation. Sexual arousal comes from sexual stimulation, and results in sexual climax (orgasm). This is the current "weather" in your emotions.

Erections are a response to a certain ratio of hormones being present in your bloodstream, which constricts the veins that exit a penis. This is a reaction to both your internal state (arousal) and external environment (temperature, physical contact, etc.)

You can have a libido without being actively aroused or without an erection. You can be aroused even with a low libido, and can be aroused without an erection. You can get an erection without arousal and with a low libido. It just so happens that all three almost always occur together.