This's one thas always been interestin' to me. I have numerous serious sleepin' problems and a tendency for disturbin', recurrin' dreams, so goin' to sleep is an issue for me and tends to affect my day pretty heavily when I wake up.

What do they mean to you?

If we go into the whole psyche and psychobabble of dreams, they talk about how [x] thing means [y]. Certain things I don't think I'll ever know how they come up w/...a woman bein' chased by a horse is supposed to imply their fear of sexual intercourse...if you're bitten by a spider it's meant to suggest confrontational problems w/ your mother.
They seem..confusin' and random.
But then others do make more sense. Dreamin' of jumpin' off a buildin' is interpreted as you takin' desperate measures to escape somethin'.

Gettin' your dreams analysed and keepin' dream journals and such can help a lot of people; the Freudian aspect of it shows that it's their subconscious tryin' to send messages to you, or that you're seein' them clearly in your unconscious state. This tends to appease some folk as they feel they can learn from it, or put the dreams to good use.
But then, we don't remember all our dreams...in fact we remember very, very few of them. What are we missin'?

If you look at it through the eyes of a scientist, they cannae fully explain it. We don't even have a clear definition of the word; currently it's hoverin' around bein' in REM sleep.
There's little to no real explanation as to what dreams are and why we have them, or specifically a certain dream, at that. There are numerous different scientific ideas and suggestions as to what they are and what causes them. Some see them as your brain takin' the chance to clean itself up, like a computer hard drive defragmentin'.
Others see dreams as interpretations of your long-term memory drive displayin' visually but w/o the reality check that consciousness brings.
They even use dreams to as a theory explain the phenomenon Deja Vu, sayin' that forgotten dreams lie dormant in your mind until you see/do somethin' that strikes up a memory and quickly recalls it to your conscious state; feelin' like a memory of somethin' that never happened...but they say that you dreamt it and simply never remembered.

The occult look at dreams in a similar aspect to the Freudian idea; important, meaningful visions that can predict the future or let you see into the heads and minds of others, or into past lives. You could hear that the future will be envisioned through a dream and have that exact situation play out later.
Scientists will argue that your brain simply remembers the more correct ones and forgets the ones that were innacurate, makin' multiple different dreams fade into the distance in favour of the most accurate.
One could counter-argue that a mere dream would not be able to predict the future regardless.

Sayin' all that, there are different types of dreams. Lucid dreams, where you are in complete control, absent-minded dreams where you feel like a viewer and not a doer, incorporated dreams where stimuli from the wakin' world creates the environment, or characters therein, that you dream about.
The sheer number of different types and ways you can dream make it seem like some neurological mess that meets no single explanation....but then you look at the consistancies...

In a single, uninterupted sleep, you're likely to dream roughly five times. Each dream tends to last no longer than half an hour.
You dream more closer to your "deep sleep" phase when your brain is at, or nearest it's most slowdown.
It's almost impossible to remember dreams that occur when your brain is at it's slowest, but as they meet the faster stages of your sleep (not long after fallin' asleep, and not long before wakin' up) it becomes easier to remember them. They follow a pattern based on the speed of your brain. Do they also differ based on this?
It's harder to remeber dreams jus' after wakin' up and they'll tend to fade away quicker, but if you're woken up by outside stimulus it's much easier to recall them; why?
People who have sleep deficiency will usually be more likely to remember their dreams than those who can sleep a full night w/o wakin' up.

Considerin' the number of changes, differences and variations alongside extremely routine patterns and structures it makes it even harder to pinpoint exactly what dreams are, what they do and what they cause. Due to this, it tends to come down pretty heavily to personal opinion.

What do dreams mean to you?