Chemical Rockets are quite expensive. They are heavy and have to carry a huge amount of fuel, and most of that fuel is consumed from getting out of orbit. These problems, which make the rocket inefficient, have caused the scientific community to search for a better solution, some have found it in ion propulsion. Like the name indicates, and ion thruster would take a propellant (like xenon) and put it through a process called electron bombardment, turning them into ions, it then goes through a grid, exiting out as an ion beam. This will save costs and money for its much more efficient. This feat of engineering is quite clever, and took a lot of work to create.
https://www.nasa.gov/centers/glenn/about/fs21grc.html
