What is the "=>" sign in LINQ queries?

Question

It's amazing how little information there is on this. I found tons of tutorials explaining LINQ, but they don't explain this particular operator:

var Results = UserFavoritesContext.UserFavorites.Select(color => color.FavoriteColor);

"x => x.y"

Can someone please explain how this works? I get the general syntax and am able to use it to make queries, but it's like doing something without knowing what you're doing.

Answer 1

Suppose you have a list of people, and you want to iterate over them. You would write something like:

foreach(var person in people)
{
       //do something to person
}

Note how you yourself chose the name person. It could've been any word, but you basically said "process every single item of the list as my person variable".

Now look at this LINQ query:

filteredPeopleList = people.Where(person => person.Name == "John");

Again, you basically chose person as a placeholder name for every object in the original list (one at a time). The above Linq query is equivalent to

foreach(var person in people)
{
       if(person.Name == "John")
       {
           filteredPeopleList.Add(person);
       }
}

To me, x => x.y is basically saying "for every variable we process (let's call it x), please perform the following operation on it (x.y, get the y property)"

I hope that explains it.

Edit
As a commenter who now deleted his comment mentioned, this isn't exclusively used in LINQ. A lambda expression doesn't have to iterate over an IEnumerable, it can be used to process a single item.
However, LINQ is by far the most common place to encounter lambdas, and I find their use very similar to the foreach loop, which is why I picked this example.