Does an SSD Make a Computer Faster?
Yes, significantly — if the computer currently has a mechanical hard drive. Startup, program loading and general responsiveness all improve noticeably, and it's usually the single biggest speed upgrade available for an older computer.
When it makes the biggest difference
The improvement is most dramatic when moving from a mechanical hard drive to an SSD — startup times and program loading can improve several times over. If the computer is generally slow and still running its original hard drive, this is usually the best first upgrade to consider.
When an SSD won't solve the problem
If the computer already has an SSD and is still slow, the bottleneck is elsewhere — usually limited RAM, too many background programs, or a genuinely underpowered processor for what you're asking it to do. An SSD upgrade won't help a computer that's already running one.