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+===================
+Crash Course in Lua
+===================
+
+Introduction
+============
+Lua is a small, but powerful language that is implemented as a library in C. This crash course in meant to help you quickly become familiar
+with Lua. This is also an opinionated introduction to Lua
+
+Key Features
+============
+* Lua is dynamically typed like Python
+* By default variables in Lua are global unless declared local
+* There is a single complex / aggregate type called a Table, which combines hash table/map and array features
+* Functions in Lua are values stored in variables; in particular functions do not have names
+* Lua has an incremental garbage collector
+* Lua is single threaded but its VM is small and encapsulated in a single data structure - hence each OS thread can be given its own 
+  Lua VM
+* Lua has integer (since 5.3) and double types that map to native C types
+* A Lua script is called a chunk - and is the unit of compilation in Lua
+* Lua functions can be yielded from and resumed later on, i.e., Lua supports coroutines
+* A special Nil value represents non-existent value
+* Functions in Lua are closures - they can capture variables from outer scope and such variables live on even though the surrounding scope
+  is no longer alive
+* Lua's error handling is based on C setjmp/longjmp, and errors are caught via a special function call mechanism
+* Lua supports operator overloading via 'meta' methods
+* Lua has a meta mechanism that enables a DIY class / object system with some syntactic sugar to make it look nice; however, you cannot 
+  explicitly declare classes in Lua
+* Lua has some nice syntactic sugar for tables and functions 
+* You can create user defined types in C and make them available in Lua
+* The Lua stack is a heap allocated structure - and you can think of Lua as a library that manipulates this stack
+* Lua compiles code to bytecode before execution
+* Lua's compiler is designed to be fast and frugal - it generates code as it parses, there is no intermediate AST construction
+* Like C, Lua comes with a very small standard library - in fact Lua's standard library is just a wrapper for C standard library
+  plus some basic utilities for Lua
+* Lua provides a debug API that can be used to manipulate Lua's internals to a degree - and can be used to implement a debugger
+* Lua is Open Source but has a closed development model - external contributions are not possible
+* Major Lua versions are not backward compatible
+* LuaJIT is a JIT compiler for Lua but features an optional high performance C interface mechanism that makes it incompatible with Lua
+
+In the rest of this document I will expand on each of the features above.
+
+Lua is dynamically typed
+========================
+This means that values have types but variables do not. Example::
+
+  x = 1 -- x is integer
+  x = 5.0 -- x is now a double
+  x = {} -- x is now an empty table
+  x = function() end -- x is now a function with empty body
+  
+
+
+