Why does this thing have a shroud?

Why does this thing have a shroud?
Is four-kay okay for a budget PC? How much should I pay for those almost 4,000 pixels?
We’ll build a sub-$1000 PC in this article. Including the monitor, keyboard, mouse, and headset, you’re looking at a cost of $700 (fully used) to $1,100 (fully new). You can also mix and match, so the total cost will be under $1,100 in most cases. There are also additional tips to bring down the cost further, taking you to $740 max.