carbocation rearrangement

We already know stability order of carbocations due to hyperconjugation, Resonance  and induction
3⁰ >2⁰> 1⁰
Now if a carbocation is less stable means 1⁰ then it can undergo rearrangement by shifting a H or  CH3  from adjacent carbon to form more stable 2⁰ or 3⁰
This is called as hydride shift or methyl shift
Hydride shift is more favorable due to less bulky nature of H then methyl group.
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