It's in Java and D as well, which likely inherited it from C. I'm pretty sure C inherited it from ALGOL's "BEGIN ... END" blocks. The catch with JS is that var

It's in Java and D as well, which likely inherited it from C. I'm pretty sure C inherited it from ALGOL's "BEGIN ... END" blocks. The catch with JS is that variable scoping rules are different when you use 'var', if you use 'let' and 'const' the scoping rules work like most programmers would expect for block statements.