Single vs double quotes in Lua

There is no difference in Lua language for quotes. You can use single or double quotes but try to be persistent within a codebase. Preferable to use double quotes because the single quote (' apostrophe) is much more often used inside the text than a double quote ". So no need to escape the sequence with \ backslash. Roblox Lua Style Guide and StyLua also recommend using double quotes.

Consider:

"5 o'clock" --- no need escape sequence
'Read "1984" book' -- double quotes inside single
"Read \"1984\" book" -- double quotes double single (escaped)

Another way to define string is to use blocks, in this case, no escape sequences are needed at all.

Consider:

[[ Start reading "1984" book as 5 o'clock ]]

Conclusion

Usually, code-style related discussions are a source of different holywars, provoked by purists and pedantists. This problem is always artificially created like this is a main problem in programming. Just choose the style of quotes that you like and use it.