This isn't quite right. That's a JPEG application specific marker (APP1). It indicates that some additional data is embedded in the JPEG file at that point which should be interpreted in an application specific manner (e.g. skipped if the program doesn't know how to handle it). That could be Exif tags but could also be other things (like XMP). An APP1 segment can be distinguished as Exif data based on the presence of the "Exif" string immediately after the segment size. (The tags themselves are stored in essentially a TIFF file embedded after the Exif identifier, if you're curious.)
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This isn't quite right. That's a JPEG application specific marker (APP1). It indicates that some additional data is embedded in the JPEG file at that point which should be interpreted in an application specific manner (e.g. skipped if the program doesn't know how to handle it). That could be Exif tags but could also be other things (like XMP). An APP1 segment can be distinguished as Exif data based on the presence of the "Exif" string immediately after the segment size. (The tags themselves are stored in essentially a TIFF file embedded after the Exif identifier, if you're curious.)