Wolfram Language & System 11.0 (2016)|Legacy Documentation
extracts the n block of characters in string, where blocks of characters are defined as delimited by whitespace.
extracts blocks at several positions in string.
takes blocks to be delimited by separators that match sep.
extracts blocks at positions posi, delimiting with whitespace for the lowest level, newlines for the next level, and a successively increasing number of newlines thereafter.
gives a nested list of blocks, with the sepi used as separators for successive levels.
Elements not present in a group yield Missing[…]: