Nobody truly knows. It is likely that - as is the case for the Earth - any water was 'delivered' there by comets.
Some tresses of water on mars .So we can say that there is water on mars
mars has flowing water on it
There was water at one time on Mars.
Water for Mars was created in 2009.
Mars has no liquid surface water.
There is no liquid water on Mars.
Mars is hot so frozen water can melt in Mars.
Mars does have water, it is just frozen in its ice caps.
Mars has water (Ice) on its polar caps
Yes. Mars use to have water like Earth's. When Mars's core cooled dramatically, the water on Mars froze.
Mars has evidence of erosion by water, including river valleys, channels, and minerals formed in the presence of water. Mars once had liquid water flowing on its surface, shaping the landscape over time.
The robots sent to Mars have found Water Ice in large quantities on the surface of Mars.