Does anyone know the term for command activated functions?

game.Players.Chatted:connect(function(msg)
if msg == "" then 
--whatever u want here
end)

game.Players.PlayerAdded:connect(msg) -- Hope it helped!

Hmm, this'll (maybe) explain how;

local Admins = {"Seaspirit89","Player1"} --Name of plaeyrs who can use the Admin

function Text(message,duration,parent,TextType) --For the 'm/' command
local m=Instance.new("Message")
m.Parent=parent
m.Text=message
wait(duration)
if m~=nil then
m:Destroy()
end
end

if game:FindService("Players")then --If game finds game.Players then
game:GetService("Players").PlayerAdded:Connect(function(plr) --Gets the service of Players, and starts the PlayerAdded event
for i,v in pairs(Admins)do --For loop for Admins
if plr.Name:lower()==v:lower() then --If name matches to Admins then
plr.Chatted:connect(function(msg) --Player can use commands

if msg:lower()=="test"then --If player chatted 'test' then
print("I'm printing a message!") --Prints a, well, print :P
end --The end

if msg:lower():sub(1,2)=="m/"then --If the msg starts with 'm/' then
Text(msg:sub(3),2,workspace,"Message") --Does a message (Type like 'm/string')
end --The end

end)
end
end
end)
end --The rest of the ends

I hope this helped!