You probably don't want to use XHTML -- it's not yet supported by IE.
target is invalid in strict HTML too. To load in a new, named window:
This is equivalent to:
For a frame (although you obviously can't use frames in Strict DOCTYPEs, just for reference):
Then there are the special ones: _self:
onclick="frames['frame_name'].location.href = this.href;"
onclick="location.href = this.href;"
onclick="top.location.href = this.href;"
onclick="parent.location.href = this.href;"