The page you are reading is part of a draft (v2.0) of the "No bullshit guide to math and physics."
The text has since gone through many edits and is now available in print and electronic format. The current edition of the book is v4.0, which is a substantial improvement in terms of content and language (I hired a professional editor) from the draft version.
I'm leaving the old wiki content up for the time being, but I highly engourage you to check out the finished book. You can check out an extended preview here (PDF, 106 pages, 5MB).
The top commands used by web programmers
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node,6731,162 for,6624,161 htop,2826,156 mysql,2839,155 rails,13571,147 svn,10609,145 time,5000,144 file,2904,143 rmdir,1472,142 bash,1858,139 sh,3084,137 gcc,5978,136 nano,5678,131 su,3918,130 heroku,8192,126 php,4960,124 s,3359,123 irb,1820,122 ./configure,1292,119 subl,6838,118 rvm,4526,117 rsync,4086,113 traceroute,1202,112 date,3521,112 tmux,6602,110 netstat,1038,110 ssh-keygen,479,109 sl,1504,105 emacs,7762,103 mount,1409,102 screen,5718,101 host,5444,99 ack,10798,98 hg,13927,96 openssl,1721,96 nslookup,1510,95 uname,449,93 nmap,1694,93 xargs,2652,93 psql,2212,93 ipython,2344,88 mplayer,14561,87 apt-cache,3580,85 go,16488,84 tree,1369,84 perl,4969,84 cut,5298,82 dmesg,1920,80 nc,2271,80 apt-get,2090,79 uptime,429,78 vagrant,4234,77 alias,1056,74 bg,2020,72 ..,4045,72 zsh,414,71 dpkg,2268,71 watch,1877,71 while,2283,71 .,836,70 rbenv,2127,70 sqlite3,1046,70 w,1141,69 more,2228,69 convert,1027,67 ssh-add,699,67 zip,651,66 ip,1868,66 pkill,867,64 tig,2027,63 gpg,2198,62 la,3426,61 rspec,3677,61 chown,585,61 ./a.out,2095,60 gdb,1475,60 gs,12493,59 g++,1640,58 evince,1562,58 gitk,2008,58 mvim,4522,58 whereis,427,58 virtualenv,424,58 c,1489,58 pgrep,1250,57 ffmpeg,1277,57 mongo,1150,57 vlc,1623,57 g,18374,56 lsof,432,56 cap,2988,55 *,3692,54 service,824,53 jekyll,1028,53 say,1331,52 historyngrep,1004,51 mate,6028,51 free,600,50 ;s,233,50 alsamixer,466,50 workon,1754,49 pdflatex,1399,49 launchctl,571,49 jobs,1019,49 javac,1297,48 umount,380,47 gedit,497,47 env,705,47 tr,1420,47 ab,955,47 defaults,500,47 foreman,2008,47 gvim,1886,47 pacman,3741,46 coffee,1719,46 wine,571,45 startx,762,45 md5sum,411,44 adb,1229,44 aptitude,1930,44 ant,917,43 unrar,699,43 dd,347,43 ghci,1224,42 mvn,2333,42 firefox,2213,42 route,243,42 lein,2177,41 reset,473,41 port,1581,41 ssh-copy-id,279,41 d,830,41 cal,941,40 whoami,98,40 crontab,612,40 cmake,855,40 easy_install,242,39 :q,326,39 if,549,39 reboot,227,39 egrep,1503,39 deactivate,296,38 redis-cli,495,38 ks,86,38 gc,4374,37 grunt,2020,37 mongod,930,37 z,2071,37 bc,1512,36 ./manage.py,4831,36 redis-server,378,36 set,939,36 valgrind,742,36 gst,7705,35 gzip,477,35 cabal,2070,35 gunzip,243,35 systemctl,816,35 strace,695,35 fab,2969,34 q,197,34 xrandr,800,34 python3,1817,34 diskutil,524,33 lsmod,189,33 ga,3210,33 mkvirtualenv,271,33 youtube-dl,2437,33 nautilus,134,33 strings,671,32 mtr,794,32 md5,165,32 hostname,125,32 compass,708,32 gco,3694,32 ftp,274,31 pushd,316,31 y,78,31 clang,2569,31 vimdiff,619,31 who,87,30 popd,216,30 gi,271,30 yes,179,30 gd,2912,29 lsusb,121,29 sftp,225,29 exec,191,29 google-chrome,980,29 lsngrep,185,28 gimp,342,28 ld,158,28 ghc,913,28 sbt,791,28 tee,595,28 shutdown,130,28 sleep,369,28 irssi,380,28 type,385,27 lspci,132,27 help,186,27 gp,1456,27 stat,396,27 django-admin.py,250,26 mosh,405,26 dscacheutil,328,26 patch,301,26 chsh,73,26 logout,184,26 sync,562,26 cd..,127,26 xclip,575,26 yaourt,7202,26 tcpdump,393,26 R,428,26 makepkg,692,26 bower,696,26 mysqldump,145,25 j,2073,25 pear,262,25 feh,738,25 mutt,7692,25 sshfs,387,25 python2,1077,25 play,350,25 yum,905,24 quit,46,24 fish,85,24 ag,4037,24 phpunit,919,24 http,2630,24 $,71,23 hexdump,584,23 be,1607,22 ldd,398,22 base64,414,22 sensors,394,22 pbcopy,312,22 createdb,155,22 apropos,178,22 octave,401,22 jar,333,22 mc,349,22 hub,480,22 iptables,294,22 pry,277,21 eog,642,21 pg_ctl,237,21 t,5595,21 printf,574,21 ipconfig,52,20 knife,3575,20 arp,177,20 rackup,319,20 sass,187,20 pod,429,20 fdisk,65,20 sublime,590,20 pulseaudio,162,20 ',161,20 v,5203,19 xit,28,19 ./install.sh,106,19 view,1093,19 postgres,154,19 #,181,19 yo,171,19 pypy,207,19 ...,163,19 rehash,349,19 py,428,19 lynx,97,19 dc,854,18 mail,376,18 m,1226,18 sysctl,216,18 """",125,18 acpi,294,18 pandoc,268,18 cls,424,18 pstree,265,18 guard,368,18 iwconfig,140,18 VBoxManage,237,18 rpm,444,18 test,88,18 xdg-open,117,17 ack-grep,2375,17 print,904,17 apachectl,182,17 mocha,531,17 android,114,17 dir,153,17 ulimit,210,17 dos2unix,122,17 gitx,956,17 passwd,36,17 hdiutil,90,17 nginx,349,16 python2.7,318,16 wireshark,138,16 RAILS_ENV=production,297,16 r,220,16 gca,1397,16 latex,137,16 id,480,16 pylint,285,16 ss,292,16 groups,42,16 p,1242,16 x,540,16 unset,83,16 scala,237,16 rtorrent,164,16 vncviewer,448,16 gnuplot,281,16 rdesktop,410,16 xkill,114,16 ~,81,16 finger,122,15 ./test,418,15 e,2255,15 express,86,15 sls,21,15 objdump,530,15 pbpaste,157,15 ssh-agent,135,15 composer,568,15 otool,356,15 meteor,362,15 unlink,376,15 rename,285,15 zeus,891,15 iostat,133,15 identify,113,15 where,74,15 [,209,15 skype,83,15 ctags,167,15 function,401,15 ncmpcpp,252,15 perldoc,809,14 cake,978,14 gl,555,14 gb,1215,14 dropbox,201,14 last,127,14 w3m,166,14 shasum,91,14 yeoman,399,14 okular,349,14 RAILS_ENV=test,193,14 s3cmd,1893,14 mysql.server,183,14 display,424,14 ./adb,385,14 purge,92,14 xxd,339,14 ./main,832,14 osascript,147,13 clang++,389,13 xmodmap,87,13 cucumber,988,13 phantomjs,223,13 gksu,50,13 siege,260,13 thin,215,13 exi,15,13 steam,158,13 cc,361,13 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