one line to remove all .log files in the current directory (rm *.log)

what if rm has been aliased to rm -i? (rm -f *.log)

copy the contents of a directory images to images_backup
(cp -r images images_backup)

view a file many pages long (less)

move two directories up (cd ../..)

execute a program encode, have it use data.txt as stdin, and use use output.txt as stdout
(./encode < data.txt > output.txt)

print a message on stderr (echo “ERROR” 1>&2)

create a directory called model_results (mkdir model_results)

suppress stdout while appending stderr
(time ./some_program > /dev/null 2>> logfile)

nice overview of most of what we’ve covered:
http://freeengineer.org/learnUNIXin10minutes.html

permissions

chmod

superuser

~

instance of a running program

contains code, resources, state

ps, top, kill

files & buffers

cutting & pasting

scrolling & windows

variables

name=value

$name

control flow

for

for var in list, for (( expr1; expr2; expr3 ))

if, while

test commands

arithmetic expansion

$(( expr ))

command substitution

$( command )

#!/bin/bash, chmod +x