Why is the first character in these variable names a '$' - JavaScript
21506
Why would a JavaScript variable start with a dollar sign?
36359
What does $# mean in shell?
59672
What are the special dollar sign shell variables?
98029
How do I access a PHP object attribute having a dollar sign?
30102
Variable name as a string in Javascript
42134
Whats the difference between "${foo.bar}" and "#{foo.bar}"?
108681
What is the $? (dollar question mark) variable in shell scripting?
23092
What does "$$" mean in the shell?
6462
Meaning of $? (dollar question mark) in shell scripts
50136
Using "${a:-b}" for variable assignment in scripts
30206
Where and how is the _ (underscore) variable specified?
133490
Dynamic variables names in javascript
142164
Why does my grep expression need to use $'string' to match tab characters?
38430
In PHP, what does the ${$ } syntax do?
35250
Why is the asterisk before the variable name, rather than after the type?
105006
What is wrong with “echo $(stuff)” or “echo `stuff`”?
60898
$(document) vs. $("document")