Javascript is an esolang commonly used in web development.
The following snippet prints hello world! in Javascript. Newlines are included for readability and can be omitted.
console.log(
"\150"+
(!!+[]+[])[~~!+[]<<~~(!+[]+!+[])]+
(null+[])[~~!+[]|(++[[]][+[]]+~~!+[])]+
([]+!!+[])[++[[]][+[]]+~~!+[]]+
([]+{})[~~!+[]]+
"\040\167"+
([]+{})[++[[]][+[]]]+
([]+!+[])[~~!+[]]+
"\154"+
([]+void(0))[(++[[]][+[]]+~~!+[])<<~~(!+[]+!+[])]+
"\041"
)