Test

<mindmap>

 "grep" [URL="http://linuxintro.org/wiki/grep" fontcolor="blue" underline=true ]
 "tr" [URL="http://linuxintro.org/wiki/tr" fontcolor="blue"]
 "wc" [URL="http://linuxintro.org/wiki/wc" fontcolor="blue"]
 "awk" [URL="http://linuxintro.org/wiki/awk" fontcolor="blue"]
 "sed" [URL="http://linuxintro.org/wiki/sed" fontcolor="blue"]
 "dialog" [URL="http://linuxintro.org/wiki/dialog" fontcolor="blue"]
 
 "Linux Shell Scripting" -> "external programs"
 "external programs" -> "grep"
 "grep" -> "dialog"
 "external programs" -> "tr"
 "external programs" -> "wc"
 "external programs" -> "awk"
 "external programs" -> "sed"
 "external programs" -> "dialog"

 "Linux Shell Scripting" -> "streams"
 "streams" -> "STDIN"
 "streams" -> "STDOUT"
 "streams" -> "STDERR"
 
 "Linux Shell Scripting" -> "reaction on CTRL_C"
 
 "Linux Shell Scripting" -> "conditions"
   "Linux Shell Scripting" -> "functions"
 "Linux Shell Scripting" -> "variables"
 
 "Linux Shell Scripting" -> "operators"
 
 "Linux Shell Scripting" -> "loops"
 
 "Linux Shell Scripting" -> "parameters"
 
 "Linux Shell Scripting" -> "string operations"

</mindmap>