1.1 Definition of Base64
Base64 is a binary-to-text encoding scheme based on 64 printable ASCII characters. Its core function is to convert arbitrary binary data into text format, making the data safe for transmission over text-only protocols.
Key Concepts:
- Encoding: Convert binary data to Base64 text
- Decoding: Revert Base64 text to original binary data
- 64 Characters:
A-Z(26),a-z(26),0-9(10),+,/(2)
1.2 Why Base64?
Historical Context
In the early days of the internet, email systems (SMTP) and many protocols only supported pure ASCII text. When users needed to send binary data like images or files, these protocols couldn't handle them directly. Base64 emerged to solve this by encoding binary as text.
Modern Use Cases
- JSON Limitations: JSON is text-only. APIs often wrap binary data (images, audio) in Base64 strings.
- Cross-Platform Compatibility: Ensures consistent binary data transmission across Windows, Linux, macOS, etc.
- Authentication: JWT (JSON Web Tokens) and HTTP Basic Auth rely on Base64.
- Database Storage: Some DBs or fields don't support binary types, requiring Base64 text storage.
1.3 What Base64 is NOT
❌ Misconception
- Not Encryption: Anyone can decode Base64. It does not protect sensitive data.
- No Security: It's just a format conversion, involving no keys.
✅ Truth
Base64 is an Encoding: Translating data from one format (binary) to another (text) for transport.
If you need privacy, use real encryption (AES, RSA) BEFORE Base64 encoding.
1.4 Pros and Cons
| Pros | Cons |
|---|---|
|
|