urls & ampersands in shell env

output.txt

$ ./test.sh http://example.org?a=b&c=d
[1] 7753
$1 is http://example.org?a=b
[1]+  Done                    ./test.sh http://example.org?a=b

$ ./test.sh "http://example.org?a=b&c=d"
$1 is http://example.org?a=b&c=d

test.sh

#!/usr/bin/env bash

echo "\$1 is $1"