| RealAudio (low fidelity sound) | Get RealPlayer | |
| control to efficiency | ||
| efficiency | ||
| new existential clause | ||
| mp3 (high fidelity sound) | Get QuickTime | |
| control to efficiency | ||
| efficiency | ||
| new existential clause | ||
| QuickTime movie | Get QuickTime | |
| [The User] @ documentation of performances | ||