**Code Golf** in JavaScript refers to attempting a problem to solve using the least amount of characters possible. Like in Golf, the low score wins, the fewest amount of characters “wins”. JavaScript is a fantastic language for code golfing due to backward compatibility, quirks, it is being a high-level language, and all the coercion. So, here we will look at some Code Golfing techniques in JavaScript language:**1. Checks if a variable is equal to some positive no:** We can simply do this with a bunch of if-else statements, but we have different methods also like subtracting that positive integer from the number and checks whether it is greater than zero or not.

**Original Code:**if(a == 5){ yes(); }else{ no(); }

**Golfed Code – I**x == 3 ? "y" : "n";

**Golfed Code – II**x-3 ? "y" : "n";

**Golfed Code – III**x^3 ? "y" : "n";

**2. Checking the case of literals:** We can even compare the literal with **{}** for checking its case, it returns **true** for the uppercase and **false** for the lowercase.

**Golfed Code:**'g' < {} // Returns false, lower case 'G' < {} // Returns true, upper case

**3. Floor the value:** A straight forward solution is used in floor function present in the Math library but it takes little more characters. We can do the same in a few characters by using the **|** operator.

**Original Code:**a = Math.floor(a);

**Golfed Code:**a = 0 | a;

**4. Ceil value:** A straight forward solution is to use ceil function present in the Math library but it takes little more characters. We can do the same in a few characters by using the combination of **%, ~** operator.

**Original Code:**a = Math.ceil(a);

**Golfed Code:**a = a%1 ? -~a : a;

**5. Rounding the value:** A straight forward solution is used to round function present in the Math library but it takes little more characters. We can do the same in a few characters by using the combination of **|, +** operator.

**Original Code:**a = Math.round(a);

**Golfed Code:**a = 0 | a + .5;

**6. Arrow functions:** Arrow functions provides a concise way to write functions in the JavaScript.

**Original Code:**g = function (a) { return a * a * a; }

**Golfed Code:**g = a => a*a*a;

**7. Alternatives for min function:** Ternary operator always saves bytes. We can compare two numbers using the ternary operator.

**Original Code:**Math.min(x, y);

**Golfed Code:**a < b ? a : b

**8. Alternatives for max function:** Ternary operator always saves bytes. We can compare two numbers using the ternary operator.

**Original Code:**Math.max(x, y);

**Golfed Code:**a < b ? b : a

**9. Absolute value:** A straight forward solution is to use absolute function present in the Math library but it takes little more characters. We can do the same in a few characters by using the ternary operator.

**Original Code:**Math.abs(x)

**Golfed Code:**x < 0 ? -x : x

**10. Save bytes in Loops:** We can save bytes by changing the variable on the last time used.

**Original Code:**for(x = 0; x < 10; x++){ alert(x); }

**Golfed Code:**for(x = 0; x < 3 ; ){ alert(x++); }

**11. Calculating Sum or Product of Array:** We have the option to do task by iterating the loop but for saving bytes we can use **eval** and arithmetic operators like **+, *, ^**etc.

**Golfed Code:**eval(a.join('+')) eval(a.join`+`) eval(a.join('*')) eval(a.join`*`)

**12. Check for NaN:** NaN method in JavaScript is used to determines whether the passed value is NaN(Not a Number) and is of the type “Number”.

**Original Code:**if(isNaN(x)){ alert(x); }

**Golfed Code:**if(x != x){ alert(x); }

**Note:** It only works if typeof(x) == “number”

**13. for vs while loops:** Both loops are efficient in terms of time complexity but when it comes to space complexity, many times **for** loop outbeats **while** loop.

**Golfed Code:**i = 10; while(i--); # While loop for(i = 10; i--; ); # For loop

**14. Combining Nested loops into a single loop:** We can combine the nested loop of 2 or more degree into a single loop.

**Original Code:**for(i = 10; i--; ) for(j = 5; j--; ) do_something(i, j)

**Golfed Code:**for(i = 50; i--; ) do_something(0 | i/5, i%5)

**15. Generating Random numbers between the range:** We can use the Date class to generate the random number because the Date is stored internally in JavaScript as the number of milliseconds since an epoch.

**Golfed Code:**new Date%1500 // Random integer 0 <= x < 1500