You decide via your subconscious mind. It sorts out what you want to remember while your conscious mind sleeps.

Nobody decides. That is why they are fun.

Great question with no answer. I would never decide to have some of the dreadful dreams I’m subjected to. They can actually ruin my mornings.

your id does the choosing.

Nobody knows much about dreams. The whys or the hows.

The Federal government.

I wish I could change what I dream about. Last night I had this horrific dream that Donald Trump was actually my boss at work and he was saying mean, terrible things to everybody and firing people left and right. I woke up in a cold sweat early in the morning and couldn’t get back to sleep.

Lucid dreaming is about controlling your dreams. You can influence what you dream about, if you develop the skill. Simply setting an intention can influence what we dream about.

Many dreams are about things your subconscious is concerned with and wants to get your attention about.

Another thing to consider is that in practicing recording my dreams, I have noticed that I seem to dream a huge amount on most nights, but only remember a fraction (even when I record a dozen dreams in one night) when I’m awake. So it might be more accurate to think of the dreams you’ve had as the few dreams you remember, and wonder why those are the ones you remember.

In my experience and in the theories of some others who have studied dreams, there seem to be other inputs as well, which have different interpretations and terms used for them. Some people talk of dream spirits visiting us, such as ancestor spirits, spirits of the land, or other sorts of external entities that can show up in dreams. Some people call some of them incubi and succubi, which is based on some Christian demonic terminology. Some dreams seem to involve premonitions or other information that’s don’t show a known relationship to our subconscious (though that’s the favorite rationalization offered by debunkers).

The Dream Master. He lives in your mind, and he comes out and the first thing he looks at out the window is what you’ll dream about.