The order in which graphics are drawn is important, as it determines which graphics appear to be on top of which other graphics.
The order in which graphical items are created is not significant to the order in which they are drawn on screen.
The most important factor for drawing order is the overlay order. All items in the first overlay are drawn before all items in the second overlay.
The next most important factor is the item level property. Using the Properties Control Bar or Properties [Home-Selection] you can change the level of items. (The level is simply a number from 0 to 255, and does not necessarily correspond to height in the real world.) Within an overlay all items with level 0 are drawn before all items with level 1, and so on.
The last factor for drawing order is the Pen style level. Every Pen is defined to be on a style level. So if two items are in the same overlay, and have the same item level, then their Pen levels will be used to determine which is drawn first.
Suppose that two items are on the same overlay, and have the same item level. Then if they use multi-level Pen objects their Pen levels will be interleaved. This can be used to achieve good cartographic effects like bordered roads, which cross over each other correctly.
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