Advantage of var keyword in C# 3.0 [duplicate]

Answer 1

The primary reason for its existence is the introduction of anonymous types in C#. You can construct types on the fly that don't have a name. How would you specify their name? The answer: You can't. You just tell the compiler to infer them for you:

var user = users.Where(u=> u.Name == "Mehrdad")
                .Select(u => new { u.Name, u.Password });