Echo

This intrinsic function converts the value of an expression to string (if necessary) and writes the string to standard output. For example:

$v1 = 23;
echo '>>'.$v1."<<\n"; // outputs ">>23<<"

$v3 = "abc{$v1}xyz";
echo "$v3\n";

For a discussion of value substitution in strings, see string literals. For conversion to strings, see type conversion.