Navigation

= __**Navigation **__ =




 * Navigation is the charting of a course for a ship or aircraft, or travel or traffic by vessels, especially in commercial shipping. It is the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Most modern navigation relies primarily on positions determined electronically by receivers collecting information from satellites.**


 * __There are several different branches of navigation, including but not limited to:__**


 * **celestial navigation - navigation by observation of the sun, moon and stars, and sometimes planets**
 * **pilot age - using visible natural and man made features such as sea marks and beacons**
 * **dead reckoning - using course and speed to determine position**
 * **Off-course navigation - allows for variables in heading by deliberately aiming to the one side of the destination.**
 * **electronic navigation - using electronic equipment such as radio navigation and satellite navigation system to follow a course to a way point Also Electronic Chart Display and Information System**
 * **position fixing - determining current position by visual and electronic means**
 * **collision avoidance using radar**


 * Navigation refers to the method used to find information within a Web site. A navigation page is used primarily to help users locate and link to destination pages. A Web site’s navigation scheme and features should allow users to find and access information effectively and efficiently. When possible, this means designers should keep navigation-only pages short. Designers should include site maps, and provide effective feedback on the user’s location within the site.**



**Navigation using bearings** ** An explanation of how planes use bearings to navigate. Navigating in a car is easy: you have roads, maps and signposts to help. When you're flying a plane there is nothing to guide you. We learn how bearings are used as an extension to the basic N, S, E and W compass points to help pilots navigate. **

Advantages:
 * -give directions
 * -good for the disabled (voice)
 * -see map in muliple views
 * -some newer GPS display real time data, by receiving and displaying traffic updates.
 * You may spend little time going around or missing a turn, the name of the street are listed on the map and the navigation system will give you enough time to prepare before your reach a turn on the road..It makes navigation easier for you

Disadvantages:
 * signal is lost in urban canyons and tunnels
 * Sometimes the GPS navigation system will get way off track and will show you completely off the road .Sometimes .this is seriously frustrating. more over, GPS navigation system often gets you within 100 yards of the location not exactly to the doorstep where you want to reach rest you have to do manually.
 * Last but not the least ,GPS navigation system is becoming an important tool for terrorism .Terrorist are misusing it to track exact place where they want to attack.