n+

Matches any string that contains at least one n

n*

Matches any string that contains zero or more occurrences of n

n?

Matches any string that contains zero or one occurrences of n

n{X}

Matches any string that contains a sequence of X n's

n{X,Y}

Matches any string that contains a sequence of X to Y n's

n{X,}

Matches any string that contains a sequence of at least X n's

n$

Matches any string with n at the end of it

^n

Matches any string with n at the beginning of it

?=n

Matches any string that is followed by a specific string n

?!n

Matches any string that is not followed by a specific string n

compile()

Deprecated in version 1.5. Compiles a regular expression

exec()

Tests for a match in a string. Returns the first match

test()

Tests for a match in a string. Returns true or false

toString()

Returns the string value of the regular expression

constructor

Returns the function that created the RegExp object's prototype

global

Checks whether the "g" modifier is set

ignoreCase

Checks whether the "i" modifier is set

lastIndex

Specifies the index at which to start the next match

multiline

Checks whether the "m" modifier is set

source

Returns the text of the RegExp pattern

array.filter(Boolean);

array.filter(x => x == 'x');

/searchString/i.test('string');

To remove everything before first /

input = input.Substring(input.IndexOf("/"));

To remove everything after first /

input = input.Substring(0, input.IndexOf("/")+1);

To remove everything before last /

input = input.Substring(input.LastIndexOf("/"));

To remove everything after last /

input = input.Substring(0, input.LastIndexOf("/")+1);

$('table tbody tr td:first-child').children('span').text(function (i) {
 return i + 1;
});

string.replace(/string/g, 'string');

$("form").reset();

array.length = num;

string.split('').reverse().join('');

Math.floor(number)