Variable names have to be meaningful. (Don't name it as "abc, i, a, b")

Method:

• use camelCase with a lowercase first letter (index, obj, getName, setName)

Object:

• use camelCase with a lowercase first letter (index, obj, getName, setName)
• Place the opening bracket on the same line as the object name.
• Use colon plus one space between each property and its value.
• Use quotes around string values, not around numeric values.
• Do not add a comma after the last property-value pair.
• Place the closing bracket on a new line, without leading spaces.
• Always end an object definition with a semicolon.

const person = {
  firstName: "John",
  lastName: "Doe",
  age: 50,
  eyeColor: "blue"
};

Class:

• camel case (Person, Student, Tutor)

Constant：

• uppercase (NUMBER, PLAYER, ABC, PLAYER_NUMBER)

Use lambda if it could be used:

var setStudent = (name,age) => {
  age +=1;
	return "name:" + name + ",age:" + age;
}

// Parentheses can be omitted when there is only one parameter
var setStudent = age => {
	age +=1;
	return "age: " + age;
}