..:: Source code - 01var_identifier.js ::..

/**
 * Variable identifier
 *  - can use any letter, digit, underscore (_) or dollar sign ($)
 *  - must start with _ , $ or letter
 *  - can't start with number
 */

//Good identifiers
var _name = 'John';
var firstName = 'Mary';
var $name = "Dollar";
var secondName2 = 'Smith';


//Bad identifiers
//var 5name = 'John'; //SyntaxError: identifier starts immediately after numeric literal

..:: NodeJS Console - 01var_identifier.js ::..

$ps -aux | grep node (list all node processes)
sasa        1197  1.2  0.6 1325404 99884 ?       Ssl  Oct18 365:50 node /home/sasa/.pm2/modules/pm2-logrotate/node_modules/pm2-logr
sasa        1211  7.7  0.7 11843840 117408 ?     Ssl  Oct18 2210:00 node /home/sasa/dex8/dex8-api/starter.js
sasa        1218  0.4  0.5 11803120 84268 ?      Ssl  Oct18 127:36 node /home/sasa/dex8/dex8-panel/server/index.js
sasa        1219  0.7  0.6 11822700 107196 ?     Ssl  Oct18 225:17 node /home/sasa/dex8/dex8-www/server/index.js
sasa        1232  0.4  0.5 11807932 91024 ?      Ssl  Oct18 132:26 node /home/sasa/mikosoft_hr/www-mikosoft-hr/server/index.js
sasa        1248  0.6  0.5 1331640 83436 ?       Ssl  Oct18 184:53 node /home/sasa/mikosoft-info/api-mikosoft-info/starter.js
sasa        1274  0.3  0.4 1300372 67916 ?       Ssl  Oct18  89:59 node /home/sasa/mikosoft-info/www-mikosoft-info/server/index.js
sasa        1277  0.3  0.3 1298544 65152 ?       Ssl  Oct18  88:34 node /home/sasa/dex8/dex8-kiosk/server/index.js
sasa        1335  0.4  0.7 11845600 122028 ?     Ssl  Oct18 131:29 node /home/sasa/mikosoft-info/dodo-mikosoft-info/server/index.js
sasa        1337  0.6  0.7 1163820 116716 ?      Ssl  Oct18 192:52 node /home/sasa/voovuu/voovuu-api/starter.js
sasa        1385  3.5  4.0 12346664 657136 ?     Ssl  Oct18 1001:14 node /home/sasa/voovuu/voovuu-pub/server/index.js
sasa        1387  0.3  0.4 11797452 81148 ?      Ssl  Oct18  97:59 node /home/sasa/@mikosoft/dodo-examples/server/index.js
sasa        1457  0.3  0.3 1101408 64332 ?       Ssl  Oct18  90:12 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1458  0.3  0.4 22278316 77864 ?      Ssl  Oct18  91:54 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1514  0.3  0.3 1101540 65176 ?       Ssl  Oct18  89:54 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1515  0.3  0.3 1101412 65044 ?       Ssl  Oct18  89:39 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1593  0.3  0.4 1101408 65632 ?       Ssl  Oct18  90:09 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1595  0.3  0.4 1101664 65532 ?       Ssl  Oct18  89:54 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1660  0.3  0.3 1101552 65312 ?       Ssl  Oct18  89:42 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1661  0.3  0.3 1101152 65032 ?       Ssl  Oct18  89:46 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1732  0.3  0.3 1101152 64788 ?       Ssl  Oct18  89:51 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1734  0.3  0.3 1101408 65388 ?       Ssl  Oct18  89:31 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1792  0.6  4.0 12368988 657324 ?     Ssl  Oct18 196:34 node /home/sasa/mikosoft-info/crypto-mikosoft-info/server/index.
sasa      367378  0.6  0.5 1331820 85144 ?       Ssl  Oct21 155:19 node /home/sasa/miko/miko-hr/api/starter.js
sasa      367471  1.1  1.5 11955240 256696 ?     Ssl  Oct21 288:35 node /home/sasa/miko/miko-hr/server/index.js
www-data 2168331  0.0  0.0   2608   592 ?        S    09:05   0:00 sh -c ps -aux | grep node
www-data 2168333  0.0  0.0   3304   712 ?        S    09:05   0:00 grep node