It was stated in Epic of Ramayana, an indian mythological story that demon lord Ravan want to build a ladder which connect Heaven and Earth so that any body can reach heaven .
Researchers from USA, Japan, and China try to build a space elevator which connect our geostationary orbit and Earth so that it will be easy to lift anything to space as all material on geostationary orbit synchronize with earth rotation.
Currently we used Rocket to send anything into the space and it was very costly nearly 20000$ to lift 1Kg of material into space.
But if we can make space elevator then cost of lifting material would be 100$/Kg.
Space Elevator: It is like a Cable/Teher which have base station near the Earth's Equator and destination end should be Earth's Geostationary Orbit.
Earth Gravity which is stronger in downside and outward/upward Centrifugal force which is stronger make cable in tension and can make it stationary in one position on Earth.
But problem to make a space elevator which connect earth geostationary orbit to earth is that we didn't have any suitable material which have the strength to withstand solar radiation , Earth' atmosphere and space debris and meteorite attack .
Another problem is that we didn't have the technology to connect the long distance of 35786 KM that is distance of our geostationary orbit from Earth.
But researcherers predicted that by 2050 they can construct a space elevator which can connect earth to geostationary orbit with approximate cost between 1billion$ to 90billion$ .
Source : https://www.google.com/amp/s/www.businessinsider.in/slideshows/miscellaneous/a-giant-elevator-could-connect-earth-to-space-using-current-technology-experts-say-heres-how-that-might-work/amp_slidelist/71467229.cms