What is Oscillator, period, frequency, amplitude?

Example 28.2 (A zoo of oscillators)

A playground swing: $T_0 \approx 3\,\mathrm{s}$. A guitar’s A string: $f_0 = 110\,\mathrm{Hz}$. A quartz crystal: $32\,768\,\mathrm{Hz}$. The cesium oscillation defining the second: about $9.2 \times 10^{9}\,\mathrm{Hz}$. Ten orders of magnitude, one job: counting.

Example 28.14 (Resonance for good and ill)

A parent pushing a swing pushes at its own frequency — resonance put to work. In $2000$ the new Millennium Bridge in London swayed alarmingly when the crowd’s steps locked onto a natural frequency near $1\,\mathrm{Hz}$; it closed two years for dampers. Every quartz watch keeps its crystal singing by driving it at resonance, $32\,768\,\mathrm{Hz}$.

Example 28.16 (Three centuries of tick)

Huygens built the first pendulum clock in $1657$: isochronism took clocks from a quarter hour of drift per day to seconds, and compensated pendulums to fractions of a second per day. The quartz wristwatch ($1969$) swapped the rod for a crystal flexing at $32\,768\,\mathrm{Hz}$: tenths of a second per month. Since $1967$ the second itself is defined by an atomic oscillation: the duration of $9\,192\,631\,770$ periods of the microwave radiation of an internal transition of cesium-133 (Chapter 34). The best cesium clocks drift one second in a hundred million years.