A simple intro to the Lua language, with everybody's favorite program, Hello World! Credit goes to Corsix.org.

HelloWorld.lua

_={_=_G}for--[[]]__--[[]]in(next),_["_"]do(_)[_]=(__)_[#_[_]],_[_[_]:byte(-#"#"
)+#_[_]-(#{}+#"(#''"*#"*#*#*"*#"_[_[]]")]=_[_],_[_]end(_)[_]=_._[_[#""]]{[_._[_
[#""]]]=_}_[""]=_._[_._[_[#[=[=#=]=]*-((#[=[#[=]#]=]))]](_._[_[-#[[_[-#[#_[_]]]
](_))]_[";"]=_._[_[#"#"+(#")#^")^#"#^"]]_["'"]=[[sub]]_['"']=_[""][_["'"]]_["/"
]=[[/_)=.,[#"('*:^;+]]_["'"]=_[""][_['"'](_[-#[[=[=]=]]],-#",_",-#"..").._["'"]
]_["["]=_['"'](_[-#"#-]_"],#",",#{_}).._['"'](_[-#"-"],#",",#"#").._['"'](_[-(#
"^#^")^#"^#"],#"-",#"(").._['"'](_[#_[-#"#"]*-#"[#"],#_[-#"#"],#_[-#"#"]).._[''
..'"'](_[-#[[=[]=]]],#_["/"]/#_["/"],#"/").._['"'](_[-(#"#)-")^#[[""]]],-#"-,",
-#[=[[]]=])_["]"]=_['"'](_[-#_[-#"-"]],#",",#"#").._[";"](_["["]..[=[('\]=]..(#
'#).'*#',..]]'*#'",#"#",'-#'(').."')")().._['"'](_[-#_[-#"-"]],-#_[-#"-"]-#"-",
-#_[-#"-"])_['_']=_[";"](_["["]..'(_[""].'.._[";"](_["["]..[[('\]]..((#_["/"]+#
"'")*#"#*("*#"..").."')")().._['"'](_[#_[-#"_"]*#"[_"],-#"#-,",-#"(,").._['"'](
_[-#_["/"]],-#",",-#"(")..'(_["/"],...,#"#","")-#"#")')_[";"](_["'"](_["'"]([[]
#/#)[([;#.))."[,[:[:[+)/,#[+#)[:[.)))^)^#/#)[([;#.))."[,[:[:[+)/,#[+#)[:[.)))^]
]],"[^".._["/"].."]",""),"(.)(.)",_[";"]("_['.'],_['#']=...".._["["].."(_['']."
.._["]"].."(_['_'](...)*#_['/']+_['_'](_['#'])))")))(...)_={#{...},#{#{}},#"#"}