About adding graphics and modifying their properties
Points, lines, circles, polygons, and rectangles are among the graphic shapes you'll use to highlight features in your data and draw cartographic elements on your layout. Once you've added a graphic to your layout, you can move it, resize it, change its color or symbol, align it with other graphics, and so on. You can also inspect its properties to find its area, length, and perimeter in the units of your choice, as well as find the x,y coordinates of point graphics and the center of polygon graphics.
Adding graphics in layout view and data view
If you want to add a graphic as part of the map layout, add it in layout view. If you want the graphic to be displayed with your data, add it in data view. For example, suppose you want to draw a circle representing a buffer around a feature. Instead of drawing the circle over the data frame in layout view, draw it directly over your data in data view. Then, as you pan and zoom your data, the circle pans and zooms with it.
When you are in layout view and want to draw graphics on a data frame so they are displayed with your data, it's not necessary to switch to data view first. Instead, click the Select Elements tool 
on the Draw toolbar and double-click the data frame. Now when you draw graphics on the data frame, they'll be added to the data frame instead of to the map layout. Once you've finished, click outside the data frame with the Select Elements tool.
Graphics you add to a focused data frame in layout view also show up in data view. However, any graphics you draw in layout view that are not being added to a focused data frame only appear in layout view.