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diff --git a/README.md b/README.md
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-# NEXRAD Level 2 Data Processing
-
+# NEXRAD Level 2 Product Processing
 
+A go application to process raw archive2 NEXRAD data and generate radar imagery.
 
 ![Hurricane Harvey after landfall](ref.png)
+Reflectivity Radar for Hurricane Harvey after making landfall from the Corpus Christy Radar site.
 
 ## Resources
 
-## Level 2 Data
+### NEXRAD
 
-> Level II data are sometimes referred to as “base data.” Level II data contain the reflectivity, radial velocity, and spectrum width data produced by the WSR-88D. For sites where the Dual Polarization modification has been completed, the following dual polarization moment data are also included: Differential Reflectivity, Correlation Coefficient, and Differential Phase. **They contain the data from all scans of the radar, at 256 data levels, and at the highest spatial resolution of the radar (1ox 1km for reflectivity, 1ox 0.25 km for radial velocity, and 1o x 0.25 km for spectrum width). At lower elevation angles (generally scans at 1.5o or lower), Super Resolution Data are produced. The difference is that Super Resolution has the following spatial resolution (0.5o x 0.25km for reflectivity, 0.5o x 0.25 km for radial velocity, and 0.5o x 0.25 km for spectrum width). In addition, Super Resolution data contain Doppler data out to a range of 300 km. For more information, go to: http://www.roc.noaa.gov/WSR88D/DualPol/DPLevelII.aspx.**
+![WSR-88D Photo](http://training.weather.gov/wdtd/courses/rac/intro/graphics/radar.jpg)
 
-### WSR-88D: Weather Surveillance Radar, 1988
+> NEXRAD or Nexrad (Next-Generation Radar) is a network of 159 high-resolution S-band Doppler weather radars operated by the National Weather Service (NWS), an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United States Department of Commerce, the Federal Aviation Administration (FAA) within the Department of Transportation, and the U.S. Air Force within the Department of Defense. Its technical name is WSR-88D, which stands for Weather Surveillance Radar, 1988, Doppler.
+> 
+> NEXRAD detects precipitation and atmospheric movement or wind. It returns data which when processed can be displayed in a mosaic map which shows patterns of precipitation and its movement. The radar system operates in two basic modes, selectable by the operator – a slow-scanning clear-air mode for analyzing air movements when there is little or no activity in the area, and a precipitation mode, with a faster scan for tracking active weather. NEXRAD has an increased emphasis on automation, including the use of algorithms and automated volume scans.
 
-![WSR-88D Photo](http://training.weather.gov/wdtd/courses/rac/intro/graphics/radar.jpg)
+> [NEXRAD: Wikipedia](https://en.wikipedia.org/wiki/NEXRAD)
 
-> The WSR-88D system was developed in the mid to late 1980s. Full scale deployment began in 1992 and was completed in 1995. DoD, DoC, and DoT jointly sponsored the development, acquisition, and deployment of the WSR-88D. There are 159 operating sites which include the RDA and RPG functional areas.
+### Archive 2 (Level 2) Data Format
 
-## Glossary
+> Level II data are sometimes referred to as “base data.” Level II data contain the reflectivity, radial velocity, and spectrum width data produced by the WSR-88D. For sites where the Dual Polarization modification has been completed, the following dual polarization moment data are also included: Differential Reflectivity, Correlation Coefficient, and Differential Phase. **They contain the data from all scans of the radar, at 256 data levels, and at the highest spatial resolution of the radar (1ox 1km for reflectivity, 1ox 0.25 km for radial velocity, and 1o x 0.25 km for spectrum width). At lower elevation angles (generally scans at 1.5o or lower), Super Resolution Data are produced. The difference is that Super Resolution has the following spatial resolution (0.5o x 0.25km for reflectivity, 0.5o x 0.25 km for radial velocity, and 0.5o x 0.25 km for spectrum width). In addition, Super Resolution data contain Doppler data out to a range of 300 km. For more information, go to: http://www.roc.noaa.gov/WSR88D/DualPol/DPLevelII.aspx.**
+
+### Glossary
 
 - **RADAR** - RAdio Detection And Ranging
 - **NEXRAD**: Next Generation Radar
@@ -25,6 +30,8 @@
 - **NetCDF** Network Common Data Form - is a set of software libraries and self-describing, machine-independent data formats that support the creation, access, and sharing of array-oriented scientific data.
 - **ICAO** International Civil Aviation Organization
 
-## Resources
-- [NOAA - Introduction to Doppler Radar](http://www.srh.noaa.gov/jetstream/doppler/doppler_intro.html) -
-- [WSR-88D Govenment Training Course](http://training.weather.gov/wdtd/courses/rac/intro/rda/index.html) - Overview of the WSR-88D Radar and system components.
+## Links
+
+- [NOAA - Introduction to Doppler Radar](http://www.srh.noaa.gov/jetstream/doppler/doppler_intro.html) - Overview of Doppler Radar Technology
+- [WSR-88D Govenment Training Course](http://training.weather.gov/wdtd/courses/rac/intro/rda/index.html) - Overview of the WSR-88D Radar and system components.
+- [NWS WSR-88D Radar Fundamentals - Slide Deck](https://www.meteor.iastate.edu/classes/mt432/lectures/ISURadarTalk_NWS_2013.pdf) - Kevin Skow National Weather Service, Des Moines, IA
diff --git a/archive2/readme.md b/archive2/readme.md
@@ -0,0 +1,39 @@
+# The Archive 2 File Format
+
+> The following is an excerpt from the `ICD for the Archive II User` document.
+
+### 7.3.6.1.1 LDM Raw Data File Format
+
+To exploit the Archive II data the end user must develop a program to extract and decompress the bz2 data stored in the LDM raw data file. Once decompressed each message requires 2432 bytes of storage with the exception of Message Type 31 (Digital Radar Data Generic Format) which is variable length.
+
+#### 1. Volume Header Record
+The first record in the file is the Volume Header Record, a 24-byte record. This record will contain the volume number along with a date and time field.
+
+#### 2. LDM Compressed Record
+
+This second record is bzip2 compressed. It consists of Metadata message types 15, 13, 18, 3, 5, and 2. See section 7.3.5. This is all related to radar site status.
+
+
+#### 3-N. LDM Compressed Record
+
+A variable size record that is bzip2 compressed. It consists of 120 radial data messages (type 1 or 31) plus 0 or more RDA Status messages (type 2). 
+
+The last message will have a radial status signaling “end of elevation” or “end of volume”. See paragraph 7.3.4. Repeat (LDM Compressed Record) Or End of File (for end of volume data) 
+
+### Message Types
+
+| Message Type | Description |
+|--------------|-------------|
+|Message 2|RDA Status Data, contains the state of operational functions|
+|Message 3|RDA Performance/Maintenance Data|
+|Message 5|RDA Volume Coverage Pattern|
+|Message 13|RDA Clutter Filter Bypass Map|
+|Message 15|RDA Clutter Map Data|
+|Message 18|RDA Adaptation Data|
+|Message 31|Digital Radar Data Generic Format|
+
+## Resources
+
+- [List of ICDs (Interface Control Documents)](https://www.roc.noaa.gov/WSR88D/BuildInfo/Files.aspx) - Consider these the documentation specs for how data is transported and processed from the Radar unit into radar products.
+- [ICD for RDA/RPG](https://www.roc.noaa.gov/wsr88d/PublicDocs/ICDs/RDA_RPG_2620002P.pdf) - The spec on the file format and field values on the archive 2 data format.
+- [INTERFACE CONTROL DOCUMENT FOR THE ARCHIVE II/USER](https://www.roc.noaa.gov/wsr88d/PublicDocs/ICDs/2620010E.pdf) - This document describes how the radar unit transfers data to the RPG (radar product generator - the thing that makes radar images). It also contains a high level overview of the Archive2 data format.