http://msmvps.com/blogs/senthil/archive/2007/11/19/type-inference-dynamic-typing.aspxLocal variable type inferencing is a new feature in C# 3.5 - a very &quot;handy&quot; one, in that it saves a lot of typing. Basically, it lets you do var dict = new Dictionary&lt;string, List&lt;int, Dictionary&lt;int, string&gt;&gt;&gt;(); instead ofenCommunityServer 2008.5 SP2 (Build: 40407.4157)http://msmvps.com/blogs/senthil/archive/2007/11/19/type-inference-dynamic-typing.aspx#1367095Wed, 28 Nov 2007 22:06:39 GMTd67277c4-116b-43f1-b688-e9ef184ea916:1367095Ben<p>C++ proposes to use the keyword &quot;auto&quot; for this reason, to indicate that the type is inferred, not that the variable is typeless.</p> <div style="clear:both;"></div><img src="http://msmvps.com/aggbug.aspx?PostID=1367095" width="1" height="1">