diff --git a/test/chan/doubleselect.go b/test/chan/doubleselect.go
index 15df249444..ac559302d9 100644
--- a/test/chan/doubleselect.go
+++ b/test/chan/doubleselect.go
@@ -4,8 +4,9 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// This test is designed to flush out the case where two cases of a select can
+// Test the situation in which two cases of a select can
 // both end up running. See http://codereview.appspot.com/180068.
+
 package main
 
 import (
diff --git a/test/chan/fifo.go b/test/chan/fifo.go
index a8dcaef8ae..70d20b31f0 100644
--- a/test/chan/fifo.go
+++ b/test/chan/fifo.go
@@ -4,7 +4,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Verify that unbuffered channels act as pure fifos.
+// Test that unbuffered channels act as pure fifos.
 
 package main
 
diff --git a/test/chan/goroutines.go b/test/chan/goroutines.go
index f52ff582af..6ffae7df65 100644
--- a/test/chan/goroutines.go
+++ b/test/chan/goroutines.go
@@ -4,8 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// make a lot of goroutines, threaded together.
-// tear them down cleanly.
+// Torture test for goroutines.
+// Make a lot of goroutines, threaded together, and tear them down cleanly.
 
 package main
 
diff --git a/test/chan/nonblock.go b/test/chan/nonblock.go
index eff1a4898c..7e3c0c74da 100644
--- a/test/chan/nonblock.go
+++ b/test/chan/nonblock.go
@@ -4,8 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Verify channel operations that test for blocking
-// Use several sizes and types of operands
+// Test channel operations that test for blocking.
+// Use several sizes and types of operands.
 
 package main
 
diff --git a/test/chan/perm.go b/test/chan/perm.go
index 89e32f1eba..7e152c5eb5 100644
--- a/test/chan/perm.go
+++ b/test/chan/perm.go
@@ -4,6 +4,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Test various correct and incorrect permutations of send-only,
+// receive-only, and bidirectional channels.
+// Does not compile.
+
 package main
 
 var (
diff --git a/test/chan/powser1.go b/test/chan/powser1.go
index 4d4882b489..6bf2a91115 100644
--- a/test/chan/powser1.go
+++ b/test/chan/powser1.go
@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Test concurrency primitives: power series.
+
 // Power series package
 // A power series is a channel, along which flow rational
 // coefficients.  A denominator of zero signifies the end.
diff --git a/test/chan/powser2.go b/test/chan/powser2.go
index 6efb358f3c..33abd5c53f 100644
--- a/test/chan/powser2.go
+++ b/test/chan/powser2.go
@@ -4,15 +4,18 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Test concurrency primitives: power series.
+
+// Like powser1.go but uses channels of interfaces.
+// Has not been cleaned up as much as powser1.go, to keep
+// it distinct and therefore a different test.
+
 // Power series package
 // A power series is a channel, along which flow rational
 // coefficients.  A denominator of zero signifies the end.
 // Original code in Newsqueak by Doug McIlroy.
 // See Squinting at Power Series by Doug McIlroy,
 //   http://www.cs.bell-labs.com/who/rsc/thread/squint.pdf
-// Like powser1.go but uses channels of interfaces.
-// Has not been cleaned up as much as powser1.go, to keep
-// it distinct and therefore a different test.
 
 package main
 
diff --git a/test/chan/select.go b/test/chan/select.go
index ce26177d54..38fa7e1e3f 100644
--- a/test/chan/select.go
+++ b/test/chan/select.go
@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Test simple select.
+
 package main
 
 var counter uint
diff --git a/test/chan/select2.go b/test/chan/select2.go
index 37a2d36a94..40bc357b5d 100644
--- a/test/chan/select2.go
+++ b/test/chan/select2.go
@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Test that selects do not consume undue memory.
+
 package main
 
 import "runtime"
diff --git a/test/chan/select3.go b/test/chan/select3.go
index 4acb93ab79..847d8ed37e 100644
--- a/test/chan/select3.go
+++ b/test/chan/select3.go
@@ -4,7 +4,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Tests verifying the semantics of the select statement
+// Test the semantics of the select statement
 // for basic empty/non-empty cases.
 
 package main
diff --git a/test/chan/select4.go b/test/chan/select4.go
index 1830150fd3..5003640385 100644
--- a/test/chan/select4.go
+++ b/test/chan/select4.go
@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file
 
+// Test that a select statement proceeds when a value is ready.
+
 package main
 
 func f() *int {
diff --git a/test/chan/select5.go b/test/chan/select5.go
index cc2cc71000..13cde1afe5 100644
--- a/test/chan/select5.go
+++ b/test/chan/select5.go
@@ -7,7 +7,10 @@
 // license that can be found in the LICENSE file.
 
 // Generate test of channel operations and simple selects.
-// Only doing one real send or receive at a time, but phrased
+// The output of this program is compiled and run to do the
+// actual test.
+
+// Each test does only one real send or receive at a time, but phrased
 // in various ways that the compiler may or may not rewrite
 // into simpler expressions.
 
diff --git a/test/chan/select6.go b/test/chan/select6.go
index 06f934e501..af470a0d0d 100644
--- a/test/chan/select6.go
+++ b/test/chan/select6.go
@@ -4,7 +4,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Issue 2075
+// Test for select: Issue 2075
 // A bug in select corrupts channel queues of failed cases
 // if there are multiple waiters on those channels and the
 // select is the last in the queue. If further waits are made
diff --git a/test/chan/sieve1.go b/test/chan/sieve1.go
index 4698dba6d6..acc310f6c7 100644
--- a/test/chan/sieve1.go
+++ b/test/chan/sieve1.go
@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Test concurrency primitives: classical inefficient concurrent prime sieve.
+
 // Generate primes up to 100 using channels, checking the results.
 // This sieve consists of a linear chain of divisibility filters,
 // equivalent to trial-dividing each n by all primes p ≤ n.
diff --git a/test/chan/sieve2.go b/test/chan/sieve2.go
index 95bf10a61f..09e5c527b6 100644
--- a/test/chan/sieve2.go
+++ b/test/chan/sieve2.go
@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Test concurrency primitives: prime sieve of Eratosthenes.
+
 // Generate primes up to 100 using channels, checking the results.
 // This sieve is Eratosthenesque and only considers odd candidates.
 // See discussion at <http://blog.onideas.ws/eratosthenes.go>.
diff --git a/test/chan/zerosize.go b/test/chan/zerosize.go
index b3fe84260c..50aca857cb 100644
--- a/test/chan/zerosize.go
+++ b/test/chan/zerosize.go
@@ -4,7 +4,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Making channels of a zero-sized type should not panic.
+// Test making channels of a zero-sized type.
 
 package main