An earthquake is a sudden shaking of the ground caused when built‑up energy in Earth’s crust is released and travels outward as seismic waves.

Quick Scoop

An earthquake happens when rocks in the Earth’s crust break or slip along cracks called faults , releasing energy that makes the ground shake. This shaking can be so small that only instruments detect it, or so strong that it damages buildings, roads, and entire cities.

How earthquakes start

  • Tectonic plates are always moving slowly, and stress builds up where they meet.
  • When the stress becomes greater than the strength of the rocks, they suddenly break or slip, causing an earthquake.
  • The point inside the Earth where this starts is the focus (or hypocenter), and the point directly above it on the surface is the epicenter.

What the shaking really is

  • The shaking is made of seismic waves that spread out from the focus, a bit like ripples when a stone is thrown into water.
  • Close to the epicenter, these waves are stronger and usually cause the most damage.
  • Sensitive instruments called seismographs record these waves and let scientists measure how big the earthquake was.

Why earthquakes matter today

  • Earthquakes remain one of the deadliest natural hazards, especially in crowded cities near major fault lines.
  • Even in the 2020s, major quakes regularly appear in global news and trigger online forum discussion about safety, early warning apps, and building standards.
  • Many guides and school essays now link basic “what is an earthquake?” explanations with real events and safety tips, reflecting how frequently they affect people’s lives.

Information gathered from public forums or data available on the internet and portrayed here.