adds some suggestions

Author: oceansize

README.md

@@ -27,7 +27,7 @@ The Command Line Murders
 
 There's been a murder in Terminal City, and TCPD needs your help.
 
-Before you start skim through the required materials in [Command Line chapter](https://github.com/makersacademy/pre_course/blob/master/command_line.md) and [Version Control Chapter](https://github.com/makersacademy/pre_course/blob/master/version_control.md). Use it as a reference while working through the mystery.
+Before you start skim through the required materials in [Command Line chapter](https://github.com/makersacademy/pre_course/blob/master/command_line.md) and [Version Control Chapter](https://github.com/makersacademy/pre_course/blob/master/version_control.md). Use it as a reference while working through the case.
 
 Now with your Terminal at hand you're ready to start. A couple of ground rules first:
 
@@ -46,9 +46,9 @@ Next you need to download those files to your machine so that you can edit them.
 
 ## Step 2: Investigate
 
-Each step of your investigation will contain the reference at the top. This reference contains the description of the commands you will need to complete the step. You can view them in the Terminal or by navigating to a file on Github.
+Each step of your investigation will contain a reference to the **Detective Handbook** at the top. Each page of the Detective Handbook contains the description of the commands you will need to complete that particular step. You can view them in the Terminal.
 
-Reference: ./reference/getting_started.md
+Reference: ./detective_handbook/getting_started.md
 
 Open a Terminal, go to the location of the files (using the `cd` command), and start by reading the file 'step0'.
 
@@ -65,4 +65,4 @@ Projects: [noahveltman.com](http://noahveltman.com)
 GitHub: [veltman](https://github.com/veltman)
 Twitter: [@veltman](https://twitter.com/veltman)
 
-Adapted by the Makers Team
+Adapted by the Makers Academy Team

reference/getting_started.md renamed to detective_handbook/getting_started.md

@@ -28,4 +28,4 @@ Git status shows what changes you have made since the last commit. The output of
 
 # `git push`
 
-After you committed the changes they still only exist on your machine. To "share" the work you need to push the changes to a remote repository. If you cloned the repository from Github you already have a remote repository setup. When you push your changes they will be pushed to Github. Type `git push` to push your commits.
+After you have committed the changes, they still only exist on your machine. To "share" the work you need to push the changes to a remote repository. If you cloned the repository from Github you already have a remote repository setup. When you push your changes they will be pushed to Github. Type `git push` to push your commits.

reference/git.md renamed to detective_handbook/git.md

@@ -1,12 +1,12 @@
 # Wildcard
 
-`ls cats/` prints out all files in the 'cats' directory. What if you only want to print out txt files? Or files with names starting with "cute_"? To do that you can use asterisk symbol:
+`ls kitties/` prints out all files in the 'kitties' directory. What if you only want to print out txt files? Or files with names starting with "cute_"? To do that you can use asterisk symbol:
 
-`ls cats/*.txt`
+`ls kitties/*.txt`
 
-`ls cats/cute_*`
+`ls kitties/cute_*`
 
-The asterisk (wildcard) is a "match all" symbol. When you type `ls cats/cute_*` command line interprets it as "print all the files in the cats directory that start with 'cute_'". The rest of the name could be anything as `*` matches all possible strings.
+The asterisk (wildcard) is a "match all" symbol. When you type `ls kitties/cute_*` command line interprets it as "print all the files in the kitties directory that start with 'cute_'". The rest of the name could be anything as `*` matches all possible strings.
 
 # `find`
 
@@ -20,7 +20,7 @@ This command works a lot just like normal English. It's saying: "find all files,
 
 `ls -a` prints all files and directories including the ones whose names begin with `.`
 
-`ls -l` prints all files as a list with all the information about files like permissions, owner, last modified time and size
+`ls -l` prints all files as a list with all the information about files like permissions, owner, last modified time and size.
 
 `ls -h` when used with `-l` option prints file size in a human readable format (Kbytes, Mbytes etc.) instead of bytes.
 

reference/step0.md renamed to detective_handbook/step0.md

@@ -0,0 +1,13 @@
+# `head`
+
+`head -N` command will print out first N lines of the file.
+
+# `tail`
+
+`tail -N` is the opposite of `head`. It will print out last N lines of the file.
+
+# `|`
+
+The pipe operator - `|` - allows you to "pipe" or direct the output of one command into the input of another command. For example if you wish to search for "British" in 'kitties.txt' and then search for "Shorthair" in the results of the first search you can use the combination of `grep` and `|`:
+
+`grep British kitties.txt | grep Shorthair`