If you're going to use several files with the same name followed by a sequence number, make the number two or three digits long. If you start with a single digit, you may not see your files in the correct order:

-document13
-document2
-document20
-document21


But you won't have this problem if you start with 001:
-document002
-document019
-document020
-document021

a related tip.

if you have a large directory of photos, and you wish to name them all relating to the theme, with a numbered ending, try the following:

CTRL + A <== this will highlight all of the images in the folder you are currently viewing
Right click on the TOP image. and choose Rename

Then type a new name for your picture set, if it is of a BBQ, then BBQ will do.
Hit Enter.

Windows will automatically rename every picture highlighted, and the directory will list as follows:

BBQ.jpg
BBQ (1).jpg
BBQ (2).jpg
BBQ (3).jpg

now all of your pictures are identified by a similar name, and given a number for sort order. it will save a lot of leg work. and you can always rename the special ones individually if you want.

Thanks guys.