The four principal techniques of navigation include dead reckoning, piloting, celestial navigation, and electronic navigation. Dead reckoning determines the position simply by coarse and speed. This is the least accurate but a very good approximation. Piloting requires plotting with geological land marks indicated on charts. There are many different ways to pilot given the information you have available. The method we will teach uses some simple geometric principles combined with the position of known objects such as buoys and landmarks in relation to a compass. Many of the buoys or markers have their own code written on them, the red buoys indicate the starboard(right) side of a channel and the black buoys indicate the port(left) side of a channel. The relationship of the position of these objects to yourself will allow a positive position on a chart known as a fix. This is the method we will be using because it is accurate and fast, but I wouldn't recommend it in the open ocean. Celestial navigation uses an instrument called a sextant. This is used to plot the angle between the horizon and a celestial object such as the sun or the north star, a very good method when out at sea, but when the horizon is always changing like in an airplane you need more instruments. Electronic navigation is fairly new to us, the radar was invented and improved upon at around the mid 1930's. In 1939 a laboratory was formed in Cambridge Massachusetts which combined what the British knew about radar and what the Americans knew, and as a result, in 1942 scientists were able to spot ships and submarines from the air, allowing the basis for anti-ship and anti-submarine radar for the U.S.. Since then electronic navigation has branched out into many devices, including global positioning systems small enough to fit in your hand.

Using the stars, sailors could measure the altitude of a star and therefor determine their position. The Octant, invented by John Hadley in the 1730's could only measure latitude, not longitude. It was replaced by John Campbell's sextant which could measure both longitude and latitude.