Markovnikov's Addition Reaction
Markovnikov's reaction follow electrophilic substitution reaction so reaction intermediate is carbocation.
Stability of carbocation = 3°>2°>1°
Markovnikov's reaction is defined as the addition of halogen takes place on the carbon having less hydrogen atom and the addition of hydrogen takes place on the carbon having more hydrogen atom this rule is given by Markovnikov ko so this rule is known as Markovnikov's rule.
This rule is applicable for only unsymmetrical alkene.
Second Definition of Markovnikov's Reaction
The negative part of reagent always attached with those double bonded carbon atom which has less number of hydrogen atoms.