Update the documentation

README

@@ -3,15 +3,21 @@ Glances -- Eye on your system
 
 ## Description
 
-Glances is a CLI curses based monitoring tool for both GNU/Linux and BSD.
+Glances is a CLI curses based monitoring tool for GNU/Linux or BSD OS.
 
 Glances uses the libstatgrab library to get information from your system.
-Glances is developed in Python and uses the python-statgrab lib.
+It is developed in Python and uses the python-statgrab lib.
 
 ![screenshot](https://github.com/nicolargo/glances/raw/master/screenshot.png)
 
 ## Installation
 
+### From package manager
+
+Packages exist for Arch, Fedora, Redhat ...
+
+### From source
+
 Get the latest version:
 
 	$ wget https://github.com/downloads/nicolargo/glances/glances-1.3.2.tar.gz
@@ -27,9 +33,10 @@ Glances use a standard GNU style installer:
 Pre-requisites:
 
 * Python 2.6+ (not tested with Python 3+)
-* python-statgrab 0.5+ (did not work with python-statgrab 0.4)
+* python-statgrab 0.5+ (did NOT work with python-statgrab 0.4)
 
-Notes: The Debian Squeeze repos only include the python-statgrab 0.4.
+Notes: For Debian.
+The Debian Squeeze repos only include the python-statgrab 0.4.
 You had to install the version 0.5 using the following commands:
 
 	$ sudo apt-get install libstatgrab-dev pkg-config python-dev make
@@ -39,8 +46,9 @@ You had to install the version 0.5 using the following commands:
 	$ ./setup.py build
 	$ sudo ./setup.py install
 
-Notes: Ubuntu 10.04 and 10.10.
-The instruction to install the version 0.5 are here: https://github.com/nicolargo/glances/issues/5#issuecomment-3033194
+Notes: For Ubuntu 10.04 and 10.10. 
+The instruction to install the version 0.5 are here: 
+https://github.com/nicolargo/glances/issues/5#issuecomment-3033194
 
 ## Running
 
@@ -50,35 +58,160 @@ Easy:
 
 ## User guide
 
-By default, stats are refrsh every second, to change this setting, you can
+By default, stats are refreshed every second, to change this setting, you can
 use the -t option. For exemple to set the refrech rate to 5 seconds:
 
 	$ glances.py -t 5
 
 Importants stats are colored:
 
-* GREEN:   stat counter is < 50%
-* BLUE:    stat counter is > 50% and < 70%
-* MAGENTA: stat counter is > 70% and < 90%
-* RED:     stat counter is > 90%
+* GREEN:   stat counter is "OK"
+* BLUE:    stat counter is "CAREFUL"
+* MAGENTA: stat counter is "WARNING"
+* RED:     stat counter is "CRITICAL"
 
 When Glances is running, you can press:
 
-* 'a' to set the automatic mode. The process list is sorted automatically
+* 'a' to set the automatic mode. The processes are sorted automatically
 
-    If CPU > 70%, sort by process CPU consomption
+    If CPU > 70%, sort by process "CPU consumption"
 
-    If MEM > 70%, sort by process size
+    If MEM > 70%, sort by process "memory size"
 
-* 'c' the processes list is sorted by CPU consumption
-* 'm' the processes list is sorted by process size
+* 'c' to sort the processes list by CPU consumption
+* 'm' to sort the processes list by process size
 * 'q' Exit
 
+### Header
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/header.png)
+
+The header shows the Glances version, the host name and the operating 
+system name, version and architecture.
+
+### CPU
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/cpu.png)
+
+The CPU states are shown as a percentage and for the configured refresh 
+time.
+
+If user|kernel|nice CPU is < 50%, then status is set to "OK".
+
+If user|kernel|nice CPU is > 50%, then status is set to "CAREFUL".
+
+If user|kernel|nice CPU is > 70%, then status is set to "WARNING".
+
+If user|kernel|nice CPU is > 90%, then status is set to "CRITICAL".
+
+### Load
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/load.png)
+
+On the Nosheep blog, Zach defines the average load: "In short it is the 
+average sum of the number of processes waiting in the run-queue plus the 
+number currently executing over 1, 5, and 15 minute time periods."
+
+Glances gets the number of CPU cores to adapt the alerts. With Glances, 
+alerts on average load are only set on 5 and 15 mins. 
+
+If average load is < O.7*Core, then status is set to "OK".
+
+If average load is > O.7*Core, then status is set to "CAREFUL".
+
+If average load is > 1*Core, then status is set to "WARNING".
+
+If average load is > 5*Core, then status is set to "CRITICAL".
+
+### Memory
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/mem.png)
+
+Glances uses tree columns: memory (RAM), swap and "real".
+
+Real used memory is: used - cache.
+
+Real free memory is: free + cache.
+
+With Glances, alerts are only set for on used swap and real memory.
+
+If memory is < 50%, then status is set to "OK".
+
+If memory is > 50%, then status is set to "CAREFUL".
+
+If memory is > 70%, then status is set to "WARNING".
+
+If memory is > 90%, then status is set to "CRITICAL".
+
+### Network bit rate
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/network.png)
+
+Glances display the network interface bit rate. The unit is adapted 
+dynamicaly (bits per second, Kbits per second, Mbits per second...).
+
+Alerts are set only if the network interface maximum speed is available.
+
+If bitrate is < 50%, then status is set to "OK".
+
+If bitrate is > 50%, then status is set to "CAREFUL".
+
+If bitrate is > 70%, then status is set to "WARNING".
+
+If bitrate is > 90%, then status is set to "CRITICAL".
+
+For exemple, on a 100 Mbps Ethernet interface, the warning status is set 
+if the bit rate is higher than 70 Mbps.
+
+### Disk I/O
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/diskio.png)
+
+Glances display the disk I/O throughput. The unit is adapted dynamicaly 
+(bytes per second, Kbytes per second, Mbytes per second...).
+
+There is no alert on this information.
+
+### Filesystem
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/fs.png)
+
+Glances display the total and used filesytem disk space. The unit is 
+adapted dynamicaly (bytes per second, Kbytes per second, Mbytes per 
+second...).
+
+Alerts are set for used disk space:
+
+If disk used is < 50%, then status is set to "OK".
+
+If disk used is > 50%, then status is set to "CAREFUL".
+
+If disk used is > 70%, then status is set to "WARNING".
+
+If disk used is > 90%, then status is set to "CRITICAL".
+
+### Processes
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/processlist.png)
+
+Glances displays a summary and a list of processes.
+
+By default (or if you hit the 'a' key) the process list is automaticaly 
+sorted by CPU of memory consumption.
+
+The number of processes in the list is adapted to the screen size.
+
+### Footer
+
+![screenshot](https://github.com/nicolargo/glances/raw/master/doc/footer.png)
+
+Glances displays a caption and the current time/date.
+
 ## Todo
 
 You are welcome to contribute to this software.
 
-* Packaging for Debian, Ubuntu, Fedora, Redhat, BSD...
+* Packaging for Debian, Ubuntu, BSD...
 * Check the needed Python library in the configure.ac
 * Add file system stats when the python-statgrab is corrected
 * Add a user guide window