What is the name of the 32-bit or 128-bit number that is used to identify a device on a network?

Which of these is most responsible for differences between the twentieth century to the twenty-first century?

My has been slow anyone else’s ?

Light travels at a speed of 186,000 miles a second. the distance light travels in a year is 5,865,690,000,000 miles/year 5,865,695,000,000 miles/year 58,656,950,000,000 miles/year 6,789,000,0000 miles/year