Microsoft Internet Explorer v8 and above installs as standard an IETLdCache INDEX.DAT file in the following location.


IETldCache in Windows XP
C:\Documents and Settings\{user}\IETldCache\index.dat
IETldCache in Windows Vista / 7


Figure 1 shows a single record from the INDEX.DAT file. 

Figure 1



These records are maintained by Microsoft and are not related to the browsing history or habits of the user.  They are present in a clean installation of the browser.  It is not known what these records are used for.

Further Reading