Check out example codes for "prevent webpage zooming in mobile". It will help you in understanding the concepts better.

Code Example 1

<meta 
     name='viewport' 
     content='width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0' 
/>

Code Example 2

<meta 
     name='viewport' 
     content='width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0' 
/>

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