The saveAsTextFile() action saves your RDD into a text file; note that each partition is a separate file. See the following snippet:

# Saves airports as a text file
#   Note, each partition has their own file

# saveAsTextFile
airports.saveAsTextFile("/tmp/denny/airports")

This will actually save the following files:

# Review file structure
# Note that `airports` is a folder with two
# files (part-zzzzz) as the airports RDD is 
# comprised of two partitions.
/tmp/denny/airports/_SUCCESS
/tmp/denny/airports/part-00000
/tmp/denny/airports/part-00001