Update README.md

README.md

@@ -16,6 +16,8 @@ _[Jump to the Electrobox Specification]()_
 
 ### Provisional Hardware/Software Abstraction Layer (HAL):
 
+The _HAL_ is a type of software hierarchial architectural design that provides generic Application Programming Interfaces for the system as abstractions with replaceable infrastructure. The _Infrastructure_ is decomposed into major bulky parts _Networking Infrastructure_, _Software Infrastructure_, and _Simulation Infrastructure (aka. IEEE-1516 HLA RTI)_. Each infrastructure is further decomposed into finer components that operate on a specific resource. _System Resources_ are either OS Resources, Hardware Resources, or Simulation Resources. Development phases are created by introducing a milestone, the milestone operates on one or more of the major bulky _infrastructures_ and brings decomposed features to the SDK gradually until the milestone is achieved.
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 ```mermaid
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@@ -69,9 +71,6 @@ columns 1
   style _OS fill:#969,stroke:#333
   style _STD fill:#999,stroke:#333
 ```
-
-### Current progress:
-
 ### Project Milestones:
 
 ```mermaid