The GNU Text Utilities

• cat - concatenate files and print to the standard output
• cksum - checksum and count the bytes in a file
• comm - compare two sorted files line by line
• csplit - split a file into sections determined by context lines
• cut - remove sections from each line of files
• expand - convert tabs to spaces
• fmt - simple optimal text formatter
• fold - wrap each input line to fit in specified width
• join - join lines of two files on a common field
• md5sum - compute and check MD5 message digest
• nl - number lines of files
• od - dump files in octal and other formats
• paste - merge lines of files
• pr - convert text files for printing
• ptx - produce a permuted index of file contents
• sort - sort lines of text files
• split - split a file into pieces
• sum - checksum and count the blocks in a file
• tac - concatenate and print files in reverse
• tail - output the last part of files
• tr - translate or delete characters
• tsort - perform topological sort
• unexpand - convert spaces to tabs
• uniq - remove duplicate lines from a sorted file
• wc - print the number of bytes, words, and lines in files
• head - output the first part of files

Manual: http://www.gnu.org/software/textutils/manual/textutils/html_node/textutils_toc.html