Comparison of ASCII, UTF-8, and UTF-16:
1. ASCII:
- Encoding Method: 7-bit binary (actually uses 8 bits, highest bit is 0)
- Character Range: 128 characters
- Storage Space: Fixed 1 byte per character
- Application Scenarios: Pure English text, simple protocols
- Advantages: Simple, efficient, good compatibility
- Disadvantages: Does not support non-English characters
2. UTF-8:
- Encoding Method: Variable-length encoding (1-4 bytes)
- Character Range: All Unicode characters
- Storage Space: ASCII characters 1 byte, other characters 2-4 bytes
- Application Scenarios: Web applications, internationalized software, modern systems
- Advantages: Backward compatible with ASCII, space-saving, widely supported
- Disadvantages: Lower random access efficiency
3. UTF-16:
- Encoding Method: Variable-length encoding (2 or 4 bytes)
- Character Range: All Unicode characters
- Storage Space: Basic Multilingual Plane 2 bytes, Supplementary Planes 4 bytes
- Application Scenarios: Windows systems, Java internal encoding
- Advantages: High efficiency for common characters
- Disadvantages: Not compatible with ASCII, byte order issues
Selection Recommendations:
- Pure English environment: ASCII
- Web/Internet: UTF-8 (recommended)
- Windows/Java applications: UTF-16