As the world population is growing, the need for fresh water is increasing. Water desalination is a mean for producing fresh water from saline water abundant in seas and oceans. Various technologies have been used to desalinate saline water with different performance characteristics. This work outlines current desalination technologies and compares their performance in terms of input and output water quality, amount of energy required, environmental impact and cost. It was found that adsorption desalination technology is a promising method for desalinating seawater due to its low running cost and low environmental impact as it uses waste energy resources.