Object snaps (Osnaps) are one of the handiest tools in AutoCAD. Without them, you would have a lot of trouble doing even the simplest dimension accurately. Before discussing how they are used, first think about what they are. Their name, "object snaps" means that they snap to objects, or more precisely, they snap to specific parts of an object. A line for example has 3 points that you can snap to: a midpoint and two endpoints. A circle has 5 points: a center and 4 quadrants. To use Osnaps effectively, you must know what points an object has that you are able to snap to.
Before you start to use the AutoCAD Modify commands, you need to know something about selecting objects. All of the Modify commands require that you make one or more object selections. AutoCAD has a whole range of tools which are designed to help you select just the objects you need. This tutorial is designed to demonstrate the use of many of the selection options. As with so many aspects of AutoCAD, developing a good working knowledge of these options can drastically improve your drawing speed and efficiency.
AutoCAD drawings are rarely completed simply by drawing lines, circles etc. Most likely you will need to Modify these basic drawing objects in some way in order to create the image you need. AutoCAD provides a whole range of modify tools such as Move, Copy, Rotate and Mirror. As you can see, the command names are easily understandable. However, the way these commands work is not always obvious. This tutorial is designed to show you how all of the Modify commands work.
To enter distances, you have been shown Absolute, Relative and Polar Co-ordinates. Now you will be shown two more ways to tell AutoCAD where the locate the point you are drawing to.
You need to know one more way changing the properties of an object. For instance, you may have made a spelling mistake in your text. You could erase it and re-create it, or you could double-click on it and just correct the error. This process is an extremely important tool to help you with your CAD work.