 <p>Everything inside the {} has access to <code>L</code>. Without the {}'s, only the next statement would have access.</p> <p>It's standard C# syntax, just like putting {}'s after an <code>if</code>, <code>for</code> or <code>while</code> statement for example. It defines a block of code that applies to the <code>using</code> statement.</p> <p>Whilst it uses the same word as an import <code>using</code>, it's use is very different. The C# language designers try to reuse reserved words, rather than introducing new ones, for backward compatibility reasons.</p> <p>In the case of a <code>using block</code>, as you are defining, the idea is that the object <code>L</code> only exists whilst the using block is executed. It is then disposed afterwards. This saves having to remember to close files or connections and generally tidy up, the using block does that for you. </p> <p>A using block is in fact just "syntactic sugar" for a try/finally block. As explained at <a href="http://msdn.microsoft.com/en-us/library/yh598w02.aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/yh598w02.aspx</a></p> <blockquote> <p>The using statement ensures that Dispose is called even if an exception occurs while you are calling methods on the object. You can achieve the same result by putting the object inside a try block and then calling Dispose in a finally block; in fact, this is how the using statement is translated by the compiler.</p> </blockquote>