Is it correct to use water instead of coolant?

Very often water is used incorrectly as an alternative to coolant, and this can lead to oxidation and wear in the machinery. Also, water freezes at 0 ºC and boils at 100 ºC. For this reason, coolants also contain glycol, which increases the boiling point and lowers the freezing point.

Related questions:

• When and how to change the car's coolant?
• What coolant should I use for my car?
• What to do if I run out of coolant?