Does the solid state hard drive still have a magnetic head?

traditional hard drives rely on the mechanical rotation of magnetic heads to read and write data.
it is said that solid-state drives have the same principle of reading and writing as memory, so solid-state drives have no heads?
then why can"t the speed catch up with memory?
is it possible that SSDs do not have magnetic heads, and the principle of reading and writing is similar to memory, but considering the cost, SSDs are made of different materials and memory, so there is also a difference in speed?
Thank you all


you're right, everything you say is right

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