What is status codes (200, 404, 500)?

When a client (like a browser or API tool) sends a request to a server, the server responds with a status code. This code tells you:

👉 “What happened to your request?”

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What is an HTTP Status Code?

An HTTP status code is a 3-digit number returned by the server to indicate the result of a request.

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1. 200 OK – Success ✅

200 means the request was successful.

When you see 200:

• Data fetched successfully
• Request processed correctly

Example:

```http id="s1"
GET /users/101 → 200 OK

👉 User data returned successfully

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##  2. 404 Not Found – Resource Missing ❌

**404** means the requested resource was **not found on the server**.

###  When you see 404:

* Wrong URL
* Resource doesn’t exist
* Invalid ID

###  Example:



```http id="s2"
GET /users/999 → 404 Not Found

👉 User doesn’t exist

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3. 500 Internal Server Error – Server Issue ⚠️

500 means something went wrong on the server side.

When you see 500:

• Code error (NullPointerException, etc.)
• Server crash
• Unexpected failure

Example:

```http id="s3"
POST /users → 500 Internal Server Error

👉 Server failed to process request

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##  Quick Comparison

| Status Code | Meaning      | Type            | Example Scenario          |
| ----------- | ------------ | --------------- | ------------------------- |
| 200         | Success      | ✅ Success       | Data fetched successfully |
| 404         | Not Found    | ❌ Client Error  | Invalid URL/resource      |
| 500         | Server Error | ⚠️ Server Error | Bug in backend            |

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##  Status Code Categories

All HTTP status codes fall into 5 groups:

| Range | Category      | Meaning               |
| ----- | ------------- | --------------------- |
| 1xx   | Informational | Request received      |
| 2xx   | Success       | Request successful    |
| 3xx   | Redirection   | Further action needed |
| 4xx   | Client Errors | Problem with request  |
| 5xx   | Server Errors | Problem on server     |

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##  Real-Time Example

Imagine using a website:

* Page loads → **200 OK** ✅
* Page not found → **404 Error** ❌
* Site crashes → **500 Error** ⚠️

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##  Why Status Codes Matter

* Help debug issues quickly
* Improve API design
* Provide clear communication between client & server
* Essential for frontend-backend interaction

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##  Conclusion

HTTP status codes are a critical part of web communication. Understanding codes like **200, 404, and 500** helps developers build and debug applications effectively.

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