You dont want to spend your entire Disneyland Vacation standing in long lines. This can be avoided by using Disneyland FastPass. FastPass can be obtained from machines located near the rides that accept FastPass. This doesnt mean that you get to immediately move to the Front Of The Line. It is more like Scheduling an Appointment for the ride later in the day at which time you actually will move to the Front Of The Line. In the meantime, you are free to go enjoy other sites and rides around the park.
When you obtain a FastPass ticket, you will be given a one hour time in which to enjoy the ride. For instance, your FastPass ticket may say 11am to 12pm. This means that you can show up and move to the Front Of The Line between the hours of 11am and 12pm. You must have your Disneyland Ticket in order to obtain a FastPass ticket.