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README.md

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-# PCS
+# PCS - P7MJ's enCryption System
+**Version:** A-1-i Proto  
+**Author:** P7MJ
 
-PCS - P7MJ's enCryption System
+PCS is a lightweight, secure Python utility designed to encrypt and decrypt ZIP files (and other binary data) using industry-standard AES-256 encryption via the Fernet protocol.
+
+## 🚀 Features
+* **Hardened Key Derivation:** Uses `PBKDF2HMAC` with **480,000 iterations** to turn your password into a cryptographically strong key.
+* **Salted Encryption:** Generates a unique 16-byte random salt for every encryption process, protecting against rainbow table attacks.
+* **Embedded Metadata:** The salt is stored directly inside the encrypted file (`.p7c_enc`), so you only need your password to decrypt.
+* **Authenticated Encryption:** Uses Fernet, which ensures that if the file is tampered with or the password is wrong, the system will refuse to decrypt rather than producing corrupted data.
+* **User Safety:** Includes file existence verification and optional "shredding" (deletion) of source files after processing.
+
+---
+
+## 🛠️ Installation
+
+PCS requires Python 3.x and the `cryptography` library.
+
+1.  **Clone or download** this repository.
+2.  **Install the dependency:**
+    ```bash
+    pip install cryptography
+    ```
+
+---
+
+## 📖 How to Use
+
+Run the script using:
+```bash
+python PCS-A-1-i-Proto.py
+```
+
+### 1. Encrypting a File
+* Select option `[1]`.
+* Enter the name of your `.zip` file (the script automatically appends the extension).
+* Create a password. **Important:** If you lose this password, your data is unrecoverable.
+* The script creates a file with the `.p7c_enc` extension.
+* Choose whether to "shred" (permanently delete) the original file.
+
+### 2. Decrypting a File
+* Select option `[2]`.
+* Enter the full name of the `.p7c_enc` file.
+* Enter your password.
+* The file will be restored as `unencrypted.zip`.
+
+---
+
+## ⚠️ Important Security Notes
+* **Password Length:** While the script is technically secure, the strength of the encryption relies entirely on the complexity of your password.
+* **The Salt:** The first 16 bytes of your `.p7c_enc` file is the salt. Do not modify or "trim" the encrypted file, or it will become undecryptable.
+* **Permanent Deletion:** The "shred" feature uses `os.remove()`, which bypasses the Recycle Bin/Trash on most systems. Use with caution!
+
+---
+
+## 🏗️ Technical Details
+* **Encryption Engine:** AES-128 in CBC mode with PKCS7 padding.
+* **Authentication:** HMAC using SHA256.
+* **KDF:** PBKDF2 with SHA256.