What is the difference between these?

I have a small question: what is the difference between these things:

(these are just examples)

local testVar = "helo" 

testVar = "helo" 

What i mean, is the "local" before the variable name, where is this needed/used ?

Thanks!

local variables have a scope limited to the block where they are declared (such as script files, functions, if statements, loops, etc).

so outside of that block they are either nil or have some other value if defined.

and testVar = "helo" will be a "global" variable for all script files in a resource (separated only by server/client side).

some examples:

  
local a = "one" -- variable is local to the script file 
b = "banana" -- variable is global for the resource 
  
outputChatBox(a) -- a is "one" 
if true then 
  local a = "two" -- adding local a variable inside "if" block 
  local c = "bleh" -- and some othe local variable 
  outputChatBox(a) -- now this a is "two" 
  outputChatBox(c) -- "bleh" 
end 
outputChatBox(a) -- outside that "if" block a is still "one" 
outputChatBox(c) -- and c is nil 
  
-- in some other same-side script file in the same resource: 
outputChatBox(a) -- nil 
outputChatBox(b) -- "banana" 
  

I already made a post noting this, please use the search next time.

local variables have a scope limited to the block where they are declared (such as script files, functions, if statements, loops, etc).

so outside of that block they are either nil or have some other value if defined.

and testVar = "helo" will be a "global" variable for all script files in a resource (separated only by server/client side).

some examples:

  
local a = "one" -- variable is local to the script file 
b = "banana" -- variable is global for the resource 
  
outputChatBox(a) -- a is "one" 
if true then 
  local a = "two" -- adding local a variable inside "if" block 
  local c = "bleh" -- and some othe local variable 
  outputChatBox(a) -- now this a is "two" 
  outputChatBox(c) -- "bleh" 
end 
outputChatBox(a) -- outside that "if" block a is still "one" 
outputChatBox(c) -- and c is nil 
  
-- in some other same-side script file in the same resource: 
outputChatBox(a) -- nil 
outputChatBox(b) -- "banana" 
  

WOW! Thanks man. Now i know exactly what those things do! Thanks !