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It is important to remember that just because you enter a parcel from survey coordinates, that doesn't mean that your resulting shapefile represents the ultimate legal description of the land ownership. Your polygon will be relatively accurate (i.e. it'll be the right shape) but not absolutely accurate (i.e. any given corner of your polygon will not necessarily be at the exact location of that point on the ground). Here are some links about accuracy and precision: [1; 2; 3]. The real accuracy of the polygon is only as good as the data you use to place and rotate the parcel. I went to a lecture recently (part of MassGIS' MGIC series) on surveying and GIS, and the presenter stressed that survey information that is entered into a GIS does not have the same legal or technical meaning as the original. Unfortunately the minutes from that presentation are not up on the web; it pointed out many important concerns with this type of data development.
A parcel survey starts at a defined point and consists of a series of line segments (or sometimes, curved lines) that usually end at the start point. Each straight line is described by a bearing, or compass direction, and a distance. These two values will be referred to as a 'survey pair' in the rest of the Help relating to surveys. Each straight line may be called a 'course'. The standard notation for the compass direction starts with either North or South and ends with either East or West. The N/S tells you which half of the 360 degree compass you are in and the E/W tells you which side of either North or South you are bearing towards. In between is a number of degrees and maybe minutes and seconds that tell you how far away from due North (or South) you are heading towards East (or West). A degree is 1/360th of a complete circle, but since the N/S and E/W have narrowed it down to one quadrant, or quarter, of the compass directions, the largest degree value possible in a survey bearing is 90. A minute is 1/60th of a degree and a second is 1/60th of a minute. So, the survey bearing N 20° 30' 00" E (the ° sign stands for degrees, ' stands for minutes, and " stands for seconds) means the survey line heads a bit more than 20 degrees to the East of due North. To head due West, a survey would say either S 90° 00' 00" W or N 90° 00' 00" W . If your survey doesn't contain bearings that look like N 30° W or S 21° 30' E or N 6° 22' 35" E (i.e. if it says 'Easterly 200 feet', or some other sort of notation) then it is not a true survey and can't be entered using these dialogs.
Some surveys include curves (this is especially common when a parcel runs along a road). There are two main types of curves: tangent curves and non-tangent curves. Tangent curves are normally described by a radius and an arc length. The curve is part of an imaginary circle; the preceding survey course is tangent to this circle at the point where the curve begins (and often the next course after the curve is also tangent to the circle as well). The radius is the radius of the circle and the length is the length of the curve. Non-tangent curves are not tangent to the course preceding them; they should have a ‘chord’ bearing and distance that you can enter into the dialog to determine where the curve should be drawn.
Tie courses are often used by surveyors to indicate areas where no exact boundaries could be marked and measured (often across a wetland, etc.). Occasionally a survey will have a tie course for each curve, so you have the option of drawing the curve as a straight line that will begin and end at the same points the curve does. Tie courses are extremely useful because they allow a survey to continue unimpeded even when the actual ground measurements are unsure.
This extension was developed to work with Massachusetts and Connecticut data. Other states and other countries may use different conventions for property surveys. In addition, it is important to know something about survey terminology in your region. For example, "by a river" may mean along the bank of a river or it may mean along the centerline of the river. Surveys use specialized terminology that may be confusing. Be careful.
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