Hi sansaephanh - Your request obliged.
- Lower string tensions generate more power
(providing string movement does not occur).
- Higher string tensions generate more ball control
(for experienced players).
- A longer string (or string plane area) produces more power.
- Decreased string density (fewer strings) generates more power.
- Thinner string generates more power.*
- More elastic strings generate more power.
- Softer strings, or strings with a softer coating, tend to vibrate less.
- Thinner strings tend to produce more spin.
- Increased string density (more strings) generates more control.
- The more elastic the string, the more tension loss in the racquet after the string job.**
* Although Wilson's research for their Sweetspot string disputes this statement.
**Pre-stretching aligns (stretches) the polymer chains in the string and "sets" the string, which reduces tension loss, albeit slightly. Generally, the more pre-stretching (prior to stringing) the less tension loss after stringing.