Probably screenshot files. In NS, pressing F5 takes a screenshot of whatever you're viewing and makes a .jpg (maybe a .tga) in your folder. It should have the map name, and then some numbers. TGAs are just image files. You could try viewing them with a program like <a href='http://www.irfanview.com/' target='_blank'>IrfanView</a> to see what they are.
They could have been produced remotely by a server executing the "screenshot" command on your client, or by accidentally hitting a key bound to "screenshot". If you don't care what's in them, they're safe to delete. If you normally get a BMP, you're using the "snapshot" command instead, which saves as "snapshot####.bmp"
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Wrote HalfLife00.tga
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They could have been produced remotely by a server executing the "screenshot" command on your client, or by accidentally hitting a key bound to "screenshot". If you don't care what's in them, they're safe to delete. If you normally get a BMP, you're using the "snapshot" command instead, which saves as "snapshot####.bmp"