Read up on it.

New York is in the Eastern Time Zone, and abides by EDT this time of year.  Some parts of the Eastern Time Zone (ET) do not abide by EDT, and they remain on Standard Time.  In the Eastern Time Zone (ET), Standard Time is represented as EST.   New York is NOT on EST.  And you can't be "in" EST.  You can be in the Eastern Time Zone, but you abide by either EDT or EST.

It's tricky.