Mathcad lets you enter equations and text anywhere in the worksheet. Each equation or piece of text is a region. Mathcad creates an invisible rectangle to hold each region. A Mathcad worksheet is a collection of such regions. To see these regions, choose Regions from the View menu. Mathcad will display blank space in gray ~d leave any regions in the default color. To turn the blank space back into the default color, choose Regions from the View menu again. To start a new region, you must first click in blank space. This leaves a small crosshair wherever you clicked the mouse. To start an equation, just start typing anywhere you put the crosshair, or choose Math Region from the Insert menu. To create a text region, first choose Text Region from the Insert menu. Whichever you do, Mathcad will place a box around the region you’re working with. In addition to equations and text, Mathcad supports a variety of plot regions. Plots are introduced in “Graphs” on page 24.