Metro
The Red line and the Green line of the Dubai Metro are almost fully operational now. It runs from about 5:50am to 11:00 pm on weekdays and slightly later on weekends (Thursday-Saturday). However, it is closed on Friday mornings and starts operation at around 1:30pm. You can find more information here. Fares range from AED 1.80 to 5.60 according to length of journey.