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![Igor Alves](https://secure.gravatar.com/avatar/a5b1aa473498cdf84e6ac7fe8e60ecf8?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Igor Alves
Courses Plus Student 4,115 PointsWhat is a session?
What exactly is a session, i didn´t underrstand?
1 Answer
![Robert Baghai](https://secure.gravatar.com/avatar/a9f9c0904d969c8ba012abd34529677d?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Robert Baghai
5,492 PointsI think you should be more specific. If you're asking about NSURLSession, at it's simplest level it is used to retrieve data from some URL. For example, if i a UIImageView in my interface and went it's image to be set as the google image at this url, https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png , I can retrieve this image via NSURLSession and use the NSData to set the image property of the imageView as UIImage imageWithData: data.