Final answer:
The only permanent solution to increase available memory on a computer is to upgrade the physical RAM by installing new memory modules that are compatible with the computer's motherboard.
Step-by-step explanation:
The permanent solution to increase the available memory on a computer is to physically upgrade the RAM (Random Access Memory). Upgrading RAM involves installing new memory modules or sticks into the available slots on the motherboard. This upgrade not only provides an immediate boost in the machine's performance but is also a permanent alteration unlike temporary solutions like closing programs or clearing temporary files. It's important to ensure compatibility between the new RAM and the existing hardware and to follow electrostatic discharge (ESD) safety precautions during installation.