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Javascript: is using 'var' to declare variables optional?
When creating variables in javascript is adding "var" before the variable name a must?
For example instead of
var message = "Hello World!"
can I use
message = "Hello World!"
?
I notice that scripts like Google Adsense don't use var
Example:
google_ad_width = 160;
google_ad_height = 600;
google_color_border = "000000";
google_color_bg = "ffffff";