Updated digital elevation model (DEM) dataset files are now given a name that includes information about the resolution and format of the data. This prevents users from accidentally overwriting existing data that might have different resolutions and formats.
an older file: n44w071.zip
would now have the name: USGS_13_n44w071.tif
indicating 1/3 arc-second elevation data in geotiff format for the 1x1 degree tile.