Good question. Some people are just content with not knowing, others are content with believing the theories of others, but few really stop to think about it.
Try this: stand up and take a look around you, walk outside or look through your window, just watch everything and take it all in. Just take a second to realize how incredible this world is, how everything works together so amazingly. How each creature has a place and a role from a horse to a bird to an ant. There are so many different species of animals, yet they are all so complex that we don't even understand it all yet. Take a look at your own body, how every part is so awesomely designed and perfectly placed. Then stop, and ask yourself this question again, "Why do we humans exist?"Did all this just, "happen" or just come from some big bang? Do you really think that everything you've just seen and thought about is just some coincidence? Some do persist to argue that this is how we exist, but that is simply because they want to stay away from any further implications of an alternative explanation. However we were most definitely created by an awesome Creator. We were placed on this Earth to look after the rest of creation, the birds, the plants, the fish and all nature. That is why we have an ability to think beyond the abilities on any other animal. At the same time through all this we exist purely to give glory and praise to our Almighty Creator in whatever we do. That is why we exist. May God be glorified through all of us.

DAVIDMOE:
Thinking about life and it's complications might make someone mad. Let's just live life, enjoy ourselves to the level we can afford; after all we will still die.

Op just go and withdraw small money from your bank account. Visit the nearest beer parlor, eat and make merry. that the meaning of life.

Asgard73:
To serve God and do his will.. through his son Jesus Christ.

Even Lucifer witches demon all humans ... will be judge on the judgement day.

Ask any witch or demon around you to confirm.

Life is simple... with Jesus.

VlamesIffect:
Brezz my brother.... Big succulent Brezz...
Brezzz is the only thing that makes me joyful for another day....