To add to what others have said, there’s logical/physical cores and virtual cores
Cores are what is meant when you hear “i7, 6 core processor”, as a general rule if your processor is an Intel brand it has i-number minus one logical cores.
Usually modern processors will have double the virtual cores which means it can host twice the amount of threads though take this with a huge grain of salt because it’s heavily dependant on the brand, line, and generation of processor
Cores are calculators, individual workers who take a set of instructions to do computations in a certain order and send the result to different slots (called registers)
Threads are those list of instructions, each core can only read one list at a time, but they can hold many inactive threads and even pass of their lists to other cores.
Those threads are like jobs, and are dispatched by a common manager who assigns work and how much time is spent on each job. You don’t have to finish a job and usually they don’t finish them in one go before they pause to share time on applications and also wait for stuff like IO (disk reads or pinging internet in the background)
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