# Understanding Comparison of Non-Numbers in JavaScript

# Understanding Comparison of Non-Numbers in JavaScript

When comparing non-numeric values, such as characters, JavaScript doesn't directly compare the letters themselves. Instead, it compares their **associated unique values**, known as **Unicode values**. These values are assigned to every character, ensuring consistent comparisons across all systems.

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## What Are Unicode Values?

Unicode is a standard that assigns a **unique code point** to every character, symbol, and even emoji. When you compare characters using comparison operators (`>`, `<`, `>=`, `<=`, etc.), JavaScript is actually comparing their Unicode values.

### Example of Unicode Values:

* **Lowercase 'p'**: Unicode value `0070`
    
* **Uppercase 'P'**: Unicode value `0050`
    

Since `0070 > 0050`, JavaScript will consider `'p' > 'P'` as `true`.

---

## Examples of Character Comparisons

### Comparing Lowercase and Uppercase Letters

When comparing `small a` to `capital A`, the comparison is based on Unicode values:

```javascript
javascriptCopyEditconsole.log('a' > 'A'); // true, because Unicode for 'a' is 97, and for 'A' is 65.
```

This behavior is consistent across all lowercase and uppercase letters.

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1737112835121/6a81c294-63ad-4ee8-ae33-0894295cb4b2.png align="center")

---

### Comparing Characters with Numeric Values

Let's look at a few more examples:

1. **Comparing digits:**
    
    ```javascript
    javascriptCopyEditconsole.log('5' > '4'); // true, as Unicode for '5' (53) is greater than '4' (52).
    ```
    
2. **Comparing lowercase letters:**
    
    ```javascript
    javascriptCopyEditconsole.log('b' > 'a'); // true, as Unicode for 'b' (98) is greater than 'a' (97).
    ```
    
3. **Comparing uppercase letters:**
    
    ```javascript
    javascriptCopyEditconsole.log('B' > 'A'); // true, as Unicode for 'B' (66) is greater than 'A' (65).
    ```
    
4. **Mixed comparisons:**
    
    ```javascript
    javascriptCopyEditconsole.log('z' > 'A'); // true, as Unicode for 'z' (122) is much greater than 'A' (65).
    ```
    

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1737113590045/40b07ed2-efed-4ac5-96a7-ea2ef2f96818.png align="center")

---

## How Unicode Affects Sorting

When sorting an array of strings or characters, the sorting is based on Unicode values:

```javascript
javascriptCopyEditlet letters = ['z', 'A', 'a', 'B'];
letters.sort();
console.log(letters); // ['A', 'B', 'a', 'z']
```

Here, uppercase letters appear bef

ore lowercase letters because of their lower Unicode values.

---

## Key Takeaways

1. **Unicode Drives Comparisons:** JavaScript uses Unicode values to compare characters, not their visual representation.
    
2. **Lowercase vs. Uppercase:** Lowercase letters always have higher Unicode values than uppercase letters.
    
3. **Sorting:** When sorting strings or characters, remember that sorting is Unicode-based. This can lead to results where uppercase letters come before lowercase ones.
    

---

## Why Is This Important?

Understanding Unicode-based comparisons is crucial when working with:

* **Case-sensitive operations:** Ensure you account for differences between lowercase and uppercase characters.
    
* **Sorting algorithms:** Know that JavaScript sorts based on Unicode values.
    
* **Internationalization:** Unicode enables consistent behavior across languages and scripts.