quotation marks in bash script around $@? : <p>I found the following snippet of bash script from <a href="https://stackoverflow.com/questions/8818119/how-can-i-run-a-function-from-a-script-in-command-line">How can I run a function from a script in command line?</a></p>

<pre><code>$ cat test.sh
testA() {
  echo "TEST A $1";
}

testB() {
  echo "TEST B $2";
}

"$@"
</code></pre>

<p>This works well. 
One of the response of this answer is <code>Use "$@" in most cases. $@ is not safe in some cases</code></p>

<p>I'm wondering why <code>$@</code> needs quotation marks, <code>"$@"</code> , in the last line.
What makes it difference with or without quotation marks around <code>$@</code> in the bash script?</p>
