The regex to add space between characters is
/(?=.)/g. This regular expression uses a positive lookahead assertion that selects each character.
You pass this regular expression as the first argument and space as the second argument to the string
"J a v a S c r i p t"
Explanation of the code:
1. In regular expression, a dot means any character. When the dot is used with a positive lookahead, it selects each character.
2. The string produced by the replace() method has a space at the beginning, so to remove that space trim() method was called.