Check out example codes for "g tag in html". It will help you in understanding the concepts better.

Code Example 1

<svg viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg">
  <!-- Using g to inherit presentation attributes -->
  <g fill="white" stroke="green" stroke-width="5">
    <circle cx="40" cy="40" r="45" />
    <circle cx="60" cy="60" r="25" />
  </g>
</svg>

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