Creating an object from a class : <p>For example</p>

<pre><code>Dictionary webster = new Dictionary();
</code></pre>

<p>what does each dictionary mean technically? I understand that I'm creating a object that has its methods and variables. But what causes this?</p>

<p>Furthermore I am learning about Data structures.. Same exact question really but can the left and right side be different? Ex</p>

<pre><code>ArrayList&lt;String&gt; list = new LinkedList&lt;String&gt;();
</code></pre>

<p>I know </p>

<pre><code>ArrayList&lt;String list = new ArrayList&lt;String&gt;(); works
</code></pre>

<p>but like I said I'm confused on what each side brings when my object is created..</p>
