Sci-fi engines that became a reality. Ion thrusters and other types of electric drives

Ion drives and other types of electric thrusters. How do they work? How different are they from conventional chemical engines? What are the pros and cons?

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Sources:
Rockets
https://www.nasa.gov/sites/default/fi...
https://www.grc.nasa.gov/www/k-12/roc...
https://www.space.com/how-rockets-work
https://courses.ess.washington.edu/es...
Types
http://www2.ee.ic.ac.uk/derek.low08/y...
Types of electric drives
https://www.sciencedirect.com/science...
https://www.sciencedirect.com/science...
Nasa’s book
https://descanso.jpl.nasa.gov/SciTech...
Raptor
https://everydayastronaut.com/raptor-...
Dawn
https://solarsystem.nasa.gov/missions...
https://solarsystem.nasa.gov/missions...
https://aip.scitation.org/doi/10.1063...
Ion drives
https://www.nasa.gov/centers/glenn/te...
https://www.nasa.gov/centers/glenn/ab...
https://www.nasa.gov/mission_pages/td...
https://www.nasa.gov/feature/glenn/20...
https://aip.scitation.org/doi/10.1063...
Spacecraft with ion thrusters
https://www.esa.int/Science_Explorati...
https://www.esa.int/Enabling_Support/...
MRO
https://mars.nasa.gov/mro/mission/spa...
NEXT
https://www1.grc.nasa.gov/space/sep/g....
DART
https://ieeexplore.ieee.org/document/...
Water
https://www.sciencedirect.com/science...
Molecular
https://iopscience.iop.org/article/10...
Iodine
https://www.nature.com/articles/s4158...
Airbreathing engines
https://www.hindawi.com/journals/ijae...