diff --git a/doc/copies.mdwn b/doc/copies.mdwn
index f647ea622d..a89376a5e4 100644
--- a/doc/copies.mdwn
+++ b/doc/copies.mdwn
@@ -7,7 +7,7 @@ to keep N copies of a file's content available across all repositories.
 
 By default, N is 1; it is configured by annex.numcopies. This default
 can be overridden on a per-file-type basis by the git-annex-numcopies
-setting in the `.gitattributes` file.
+setting in `.gitattributes` files.
 
 `git annex drop` attempts to check with other git remotes, to check that N
 copies of the file exist. If enough repositories cannot be verified to have
diff --git a/doc/git-annex.mdwn b/doc/git-annex.mdwn
index 65cce8cc29..09282e7213 100644
--- a/doc/git-annex.mdwn
+++ b/doc/git-annex.mdwn
@@ -238,7 +238,7 @@ Many git-annex subcommands will stage changes for later `git commit` by you.
 
 # CONFIGURATION
 
-Like other git commands, git-annex is configured via `git-config`.
+Like other git commands, git-annex is configured via `.git/config`.
 Here are all the supported configuration settings.
 
 * `annex.uuid` -- a unique UUID for this repository (automatically set)
@@ -267,7 +267,7 @@ Here are all the supported configuration settings.
   between versions.
 
 The backend used when adding a new file to the annex can be configured
-on a per-file-type basis via the `.gitattributes` file. In the file,
+on a per-file-type basis via `.gitattributes` files. In the file,
 the `git-annex-backend` attribute can be set to the name of the backend to
 use. For example, this here's how to use the WORM backend by default,
 but the SHA1 backend for ogg files:
@@ -276,14 +276,14 @@ but the SHA1 backend for ogg files:
 	*.ogg git-annex-backend=SHA1
 
 The numcopies setting can also be configured on a per-file-type basis via
-the `git-annex-numcopies` attribute. For example, this makes two copies
-be needed for ogg files:
+the `git-annex-numcopies` attribute in `.gitattributes` files.
+For example, this makes two copies be needed for wav files:
 
-	*.ogg git-annex-numcopies=2
+	*.wav git-annex-numcopies=2
 
 # FILES
 
-These files are used, in your git repository:
+These files are used by git-annex, in your git repository:
 
 `.git/annex/objects/` contains the annexed file contents that are currently
 available. Annexed files in your git repository symlink to that content.
diff --git a/doc/walkthrough.mdwn b/doc/walkthrough.mdwn
index 281f460506..9d4d2ce594 100644
--- a/doc/walkthrough.mdwn
+++ b/doc/walkthrough.mdwn
@@ -339,3 +339,31 @@ might say about a badly messed up annex:
 	git-annex: Only 1 of 2 copies exist. Run git annex get somewhere else to back it up.
 	failed
 	git-annex: 2 failed
+
+## backups
+
+git-annex can be configured to require more than one copy of a file exists,
+as a simple backup for your data. This is controled by the "numcopies"
+setting, which defaults to 1 copy. Let's change that to require 2 copies,
+and send a copy of every file to a USB drive.
+
+	# echo "* git-annex-numcopies=2" >> .gitattributes
+	# git annex copy . --to usbdrive
+
+Now when we try to `git annex drop` a file, it will verify that it
+knows of 2 other repositories that have a copy before removing its
+content from the current repository.
+
+You can also vary the number of copies needed, depending on the file name.
+So, if you want 3 copies of all your flac files, but only 1 copy of oggs:
+
+	# echo "*.ogg git-annex-numcopies=1" >> .gitattributes
+	# echo "*.flac git-annex-numcopies=3" >> .gitattributes
+
+Or, you might want to make a directory for important stuff, and configure
+it so anything put in there is backed up more thoroughly:
+
+	# mkdir important_stuff
+	# echo "* git-annex-numcopies=3" > important_stuff/.gitattributes
+
+For more details about the numcopies setting, see [[copies]].