Why do scientists look for water when looking for life? What are the properties of water that are important for sustaining life? Could there be life on other planets without water?

Ever since NASA was established in 1956, humans have been looking for life beyond Earth. The effort in looking for life elsewhere in our solar system involves looking for the presence of water. Why do scientists look for water when looking for life? What are the properties of water that are important for sustaining life? Could there be life on other planets without water?

Article/Podcast–This is Why Water is Essential for Life on Earth…and Perhaps the Rest of the Universe (Science Focus) (Links to an external site.)
and The Amazing Properties of Water (NRICH) (Links to an external site.)