In Islam, the direction towards which all Muslims face when performing their prayers is called the Qibla, and it points towards the city of Mecca and specifically to the Kaaba. The Qibla serves as a symbol of unity among Muslims and is the direction towards which Muslims offer their obligatory prayers, five times a day, every day. To determine the proper direction, one has to know with some precision both the longitude and latitude of ones own location and those of Mecca, the city toward which one must face. Muslims can use a Qibla compass, which is a compass that points towards the Qibla direction. Alternatively, Muslims can use Qibla finder apps or websites that use GPS technology to determine the users location and calculate the Qibla direction. If a Muslim is in outer space or in a location where determining the Qibla direction is difficult, they can start in the direction which to the best of their knowledge is Mecca and continue the prayer even if the direction changes.