< script />之间的区别和< script>< / script>用于在HTML中导入多个js文件

我最近遇到的这个问题，我试图在我的HTML页面中导入多个js文件 -

This issue I recently faced, I was trying to import multiple js files in my HTML page like this -

<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore.js" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.js" />
<script src="lib/js/backbone.js" />

但是我面对的问题是，它只加载第一个js文件，其余的js文件没有被加载。我也在浏览器中检查了网络部分，剩下的两个文件只是没有被调用。然后我改变了语法 -

But the issue I was facing is, it was loading only the first js file and the rest of the js file was not getting loaded. I also checked the network section in the browser, the remaining two file was just not getting called. Then I changed the syntax to this -

<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.js"></script>
<script src="lib/js/backbone.js"></script>

然后所有3个文件的加载成功发生。我的问题是，是

And then the loading of all the 3 files happened successfully. My question is, is

<script src="" /> 

错误的语法或者这个问题只针对我？

a wrong syntax or is this issue only specific to me?