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LINQ (Language-Integrated Query) allows you to use a range of powerful querying capabilities directly in the C# language. Using LINQ, we can filter by age using Where, Map from a Person object to the name string using Select and Evaluate the query to a list using ToList. This is known as deferred execution, since you don't have to execute the query on the whole data set at once. This gives you additional power to create more complex queries. It is expected that deferred execution will result in better performance, since it doesn't need to be immediately executed.