object ids of system objects in sql server

Try this:

in sql server 2005

use master

go

select * from sysobjects where id<0

total 1773 rows returned and the ids are like the below: But why do the system objects have -ve ids???

-1042000603
-1041222755
-1037786908

..

..

Also fire the below query

select xtype,count(xtype) from sysobjects where id<0 group by xtype

the result is:

xtype    (No column name)
FN    27
IF    19
P     1277
PC    3
TF    12
V     286
X     149

in sql server 2008

select * from sysobjects where id<0

total rows returned are 1927

select xtype,count(xtype) from sysobjects where id<0 group by xtype

xtype    (No column name)
AF    1
FN    38
FS    4
IF    30
P     1348
PC    3
TF    13
V     354
X     136

 

in sql server 2008R2

select * from sysobjects where id<0 

 total rows returned are 1928

select xtype,count(xtype) from sysobjects where id<0 group by xtype
order by xtype

 

xtype    (No column name)
AF    1
FN    38
FS    4
IF    30
P     1348
PC    3
TF    13
V     354
X     137