Grace Murray Hopper invented it
I'm assuming hardware.
Remember, Hard = Physical.
If that's not it, try peripherals.
This is called a "heat sink", essentially, a metal plate makes indirect <span>(its separated by thermal paste)</span> contact with the heat spreader of a cpu (central processing unit). The concept is that the heat sink is made of highly conductive materials thus conducting heat away from the CPU, quite often you'll find a fan attached to further disparate heat away from the heat-sink. These days you'll alternative cooling methods, the most common alternative is to use watercooling (another topic). GPU (graphic processing units) also have heatsinks.
Answer:
A waveform that switches representing the two states of a Boolean value (0 and 1, or low and high, or false and true) is referred to as a digital signal or logic signal or binary signal when it is interpreted in terms of only two possible digits.
