I’ll focus on the differences to the consumer.
SSDs are much, much faster. They can be 10 to 1000x times faster. Your computer will run silky smooth.
HDDs will store a little more data for the cost. Maybe 2-4x.
SSDs shouldn’t be filled up, as it reduces write speed, but not read speed. 50% is fine, but I won’t go over 75%.
Personally I’m using an SSD and being careful not to overload it with stuff. I delete stuff that I download when I no longer need it.
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