The key to Point of Sale Applications is the use of various operating systems for recording and registering the items rendered per room. Most hotels have applied the use of the Windows operating system in their computers while others have applied Unix as their main console for their POS systems. The data used by the cashier would then be registered through local data storage or through various computers for easier assessment and evaluation. Today, most hotels have even applied a membership connection through internet so that hotel customers would be able to register to a room that they want simply by accessing the hotel's website. With the use of a cellphone or a laptop, customers can order the food that they want so that if they would plan to check in, the food would already be on the counter. For hotels that have extra charges such as a masseuse or a cleaning lady, the POS systems would also be able to record such services and then create a receipt if the customer would plan to check out. That is why a Point of Sale system is very important not only in hotels but also in any kind of business.