A Windows SID is a numeric identifier used to represent Windows accounts.
A Windows SID is a numeric identifier used to represent Windows accounts. SIDs are commonly represented using a textual format such as S-1-5-21-1496946806-2192648263-3843101252-1029 but they may also be resolved to yield the name of the associated Windows account such as Administrators or MYDOM\alice.
Consider the following output of examples/SidLookup.java: