What does "L", "[" and ";" mean in smali code?

What does "L", "[" and ";" mean in smali code?

I'm trying to get a deep understanding of smali language. I found a page
talking about opcodes online, but it never talks about these special
symbols, which is L, ; and [, e.g
invoke-static {v2, v3},
Ljava/lang/String;->format(Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/String;
So, what does these symbols mean here? e.g [Ljava/lang/Object; and
Ljava/lang/String;