An SSD usually makes a computer start, open applications and access files much faster than a mechanical hard drive. NVMe SSDs can be faster than SATA SSDs, but the computer must support the correct interface.
Hard drives remain useful when large capacity is needed at a lower price, especially for archives and backup copies. Mechanical parts make them more sensitive to impact and slower for active operating-system use.
Confirm format, interface and capacity before purchase. Keep important information in more than one place; changing to an SSD improves speed but does not replace a proper backup plan.
