In this case, we have to start with the <u>protonation</u> of the "OH" group by the attack of the lone pairs in the alcohol group to the "H" in the HBr producing a <u>positive charge in the oxygen</u>. Then, water is produced and a <u>carbocation</u> is generated. This carbocation can be stabilized by a <u>hydride shift</u>. We can move a hydrogen atom to the positive charge and we will obtain a <u>tertiary carbocation</u>. Finally, the will attack to produce the final <u>halide</u>.