Look up the sky what do you see ? Hmmmm..... hard to tell there are too many things to portray, isn't it ? The basic point is that we have a lot of things before us to see , know but what if i say you that what we i.e. humans can see is only the 5% of everything ?
Yes , its true according to researches and studies that the observable universe for us is just a meagre 5% , wtf ? Where is the rest of universe then , well is it there or not ?
The answer is its definitely there but we are until now not eligible to have a visionary perspective about it . Well according to studies our universe is composed of 73% dark energy , 22% dark matter , and 5% visible matter which is the observable universe.
Now, the question is what the hell is dark energy and dark matter ?
Hmmm.... the answer is somehow controversial but fairly substantial , we don' t know what dark energy and dark matter is but we definitely know that its there because we can see its effects on our universe . Some physicists say that dark energy is the reason for the expansion of our universe which we can detect due to the red shift effect , while some say dark energy is nothing but gravity ! Gravitational pull from other universes outside our own , hence we would never to see it because these universes are parralel to each other , hence impossible to detect .
Let's make it easy we don't see wind do we? But we can certainly feel and see it's effects , now coming to dark matter , from the name itself it suggests that it is dark so undetectable . It is the matter which we can't detect but it has matter like properties. So now we know that there is another type of matter - Dark Matter.
Confused ! Well this is how our universe is . Confusing still scintillating.