diff --git a/man7/pthreads.7 b/man7/pthreads.7
index 9c7644d4c..1b4a3bb6c 100644
--- a/man7/pthreads.7
+++ b/man7/pthreads.7
@@ -21,7 +21,7 @@
 .\" Formatted or processed versions of this manual, if unaccompanied by
 .\" the source, must acknowledge the copyright and authors of this work.
 .\"
-.TH PTHREADS 7  2008-10-16 "Linux" "Linux Programmer's Manual"
+.TH PTHREADS 7  2008-11-07 "Linux" "Linux Programmer's Manual"
 .SH NAME
 pthreads \- POSIX threads
 .SH DESCRIPTION
@@ -113,6 +113,20 @@ Note that the pthreads functions do not set
 For each of the pthreads functions that can return an error,
 POSIX.1-2001 specifies that the function can never fail with the error
 .BR EINTR .
+.SS Thread IDs
+Each of the threads in a process has a unique thread identifier
+(stored in the type
+.IR pthread_t ).
+This identifier is returned to the caller of
+.BR pthread_create (3),
+and a thread can obtain its own thread identifier using
+.BR pthread_self (3).
+Thread IDs are only guaranteed to be unique within a process.
+A thread ID may be reused after a terminated thread has been joined,
+or a detached thread has terminated.
+In all pthreads functions that accept a thread ID as an argument,
+that ID by definition refers to a thread in
+the same process as the caller.
 .SS "Thread-safe functions"
 A thread-safe function is one that can be safely
 (i.e., it will deliver the same results regardless of whether it is)