GNU Command
$> a1.txt
$a > a2.txt
bash: a: command not found
$echo a > a2.txt
$ls -S
a2.txt a1.txt
$ls -S -1
a2.txt
a1.txt
$ls -r -S -1
a1.txt
a2.txt
$
UNIX Explanation
-S sort by file size
-1 list one file per line
-r, --reverse
reverse order while sorting
computer science Theory Drop
Sorting is any process of arranging items in some sequence and/or
in different sets, and accordingly, it has two common, yet distinct
meanings: ordering: arranging items of the same kind, class,
nature, etc. in some ordered sequence, categorizing: grouping and
labeling items with similar properties together (by sorts).
source : http://en.wikipedia.org/wiki/Sorting
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