Regardless of the physical medium (SSD vs spinning disk) data is read in pages, in much the same way data from main memory is read to the CPU caches in chunks (

Regardless of the physical medium (SSD vs spinning disk) data is read in pages, in much the same way data from main memory is read to the CPU caches in chunks (called cache lines). Reading from either source byte by byte is extremely slow. Intuitively then, reading adjacent bytes on a disk will be faster. No matter how fast reading the page is, reading one page is always going to be faster than reading two. SSDs make random access faster than compared to a spinning disk (lower latency/seek time) but it can't break the laws of physics and make two seeks the same cost as one.