What are the advantages and disadvantages of punishment in schools and colleges?
This varies with the type of punishment. Corporal punishment is a form of child abuse and tends to breed violence and bullying. Numerous studies show that corporal punishment increases rather than prevents delinquent, criminal, and antisocial behavior. It also leads the child to be more likely to grow up to commit child abuse and domestic violence. There really are no advantages to corporal punishment or even bullying and verbal abuse.
Other forms of punishment, when used appropriately, can help dissuade students from certain types of bad behavior. For example, if a student plagiarizes an assignment, giving the student a failing grade can dissuade the student from future plagiarism. For punishments to work, they must quickly follow on the offense, be applied fairly, and fit the offense. Punishments should not be seen as intended to harm the student or express anger but rather as part of a consistent rule system that encourages certain behaviors and discourages others. Punishments for bad behaviors should be balanced by rewards for good behaviors to avoid discouraging students. For example, you can be strict about giving bad marks for plagiarism while giving high marks for good research.
If students are disruptive in a way that interferes with other students' learning, it is sometimes necessary to expel them from class; if such behavior persists, suspension or expulsion from school may be necessary. I'm not sure that it is best to think of those acts as "punishment" per se, though, but rather I think we should frame such disciplinary measures as simply part of effective classroom management. I don't think of removing a disruptive student as "punishment" but simply as a necessary step to make the classroom function in an optimal fashion.
Punishment is an event that takes place after a behavior. Punishments are designed to reduce that behavior in the future. If you are pulled over for a speeding ticket, that ticket is a punishment designed to reduce your behavior of speeding—or at least speeding when a police officer is nearby. Prison is designed to be a punishment for crimes, as is getting sent to the principal's office for breaking school rules.
While punishment can work in the short term, it does tend to have a negative effect on relationships between the punisher and the punished, especially if the person doing the punishment has made some kind of mistake. Children who are punished over and over again lose interest in school and tend to drop out.
When punishment is frequent, a person may believe nothing he or she does will be successful and may quit trying. This is known as learned helplessness and makes learning almost impossible.
Finally, some people become used to punishment, which means the consequence do not work as a deterrent to behavior. The child who knows the teacher will reliably yell under certain circumstances may actually deliberately commit undesirable behaviors with the purpose of making their teacher angry. The punishment, in this case, actually increases the problematic behavior.
There are always going to be cases where punishment is merited, such as when a behavior is dangerous or seriously egregious. A better way of dealing with relatively minor infractions, though, is to figure out why the person is doing these things and to help that person both understand why the behavior is problematic and voluntarily commit to doing something better.