With the 2006 version of HTMLPad, when you save a file it creates a file called myfilename.shtml.bak. If it is saved again, then the old .bak file is erased and replaced with a new .bak; thus, you get only one generation of backup.
I much the NoteTap Pro file backup solution. If the most recent file is
index.shtml
the one that it replaced is
~index[003].shtml ... and the one it replaced is
~index[002].shtml ... and the one it replaced (the one you started with) is
~index[001].shtml
Thus, if you really mess up, you can go back to where you started, or to any of the interim backups along the way. At the end, you can alpha sort your subdirectory and the ~ characters will float to the top, where you can erase some or all as you feel led ...