I vaguely remember having read somewhere that when a 100-year old woman was interviewed, what is one thing she had to say. She laughed and said, "at 100, I do not face any peer pressure."
The moment a child is out of the womb, the one thing that constantly follows him/her is peer pressure. My baby's weight is only 2.5 kg, while her baby's weight is 3 kg. We will not say that it is peer pressure, but comparison. If a baby's weight falls within normal, there is no need to worry that it is underweight and weak. But when relatives or friends start telling about the weight to the new parents, it will set them thinking.
As per Wikipedia, peer pressure usually sets in during adolescent stage, when students feel pressure to perform better in studies and other activities. The toppers will be the envy of other students in the class. Smart students will form a group and they may not mingle or interact with other classmates in their class. Parents will want their average child to perform better than those brilliant classmates. This puts unnecessary stress and pressure on the child.
Now with the changing scenario compared to about 3 decades back, the child will feel the pressure as early as the age of 5. Today's child is born with video gadgets, cartoon characters like Chotta Bhim, friendly Ganesha, Scooby Doo, Mr Bean, Bugs Bunny, Tom and Jerry, Mickey Mouse, to name a few. These days, it does not end with watching programs of these characters. Marketers make lots of toys, gadgets, T-shirts, bedspreads et al, anything related to these cartoon characters attractive enough in a child's eyes. It goes without saying that if a child sees his/her friend having that item, then the child will press his/her parents adamantly till he gets a similar one like that. If that child goes to any birthday party, he/she will notice the themed cake, gifts, the extravaganza and starts making demands for that. These are all peer pressures relevant to that age.
As the child enters teens, he/she will lose interest in cartoons and birthday parties conducted by their parents and other priorities take over. Academics become a top priority, and the child always feels the pressure to excel in the class. This is where parents and teachers should see that the child's self esteem is not lowered and they should strive to bring the individuality in him/her. Sometimes the peer pressure may work out in a positive manner when the child himself wants to improve upon himself either in sports or academics or anything other than that.
Teenage or adolescent stage is the phase when the individual is neither a child nor an adult. During this period, he/she undergoes lot of changes mentally and physically and the personality is mostly cemented. This is the vulnerable age when he/she starts smoking and drinking just to please his friends. What starts off just for fun may become lifelong habits which will affect the health of that individual and his/her family. With our society becoming more westernized, teenagers feel that they will be left out of the crowd, if they do not have girlfriends/boyfriends. This is when he/she would have learnt driving and just to feel the thrill of it, lot of rash driving is done leading to accidents and death. This is when parents feel generation gap, especially when their wards do not listen or talk to them. Teenagers are like brittle glass objects who need to be handled with utmost care.
Adulthood has different pressures to offer. Once the teenagers become adults, they see their peers getting married and settle down to family life. Many of the teenagers repel at the idea of married life. But later on, they eventually fall in the 'trap' of marriage. Then of course, there is always pressure to have 'good' careers and high-paying jobs, promotions. Women always feel the constant pressure to have a perfect family, good career and job. Since managing house, children is still considered a woman's job, juggling all these multiple roles put lot of stress and pressure and if they are not handled properly, it will lead to fatigue and health problems later on. Men who are still considered main breadwinners, always try to have jobs with steady income, even if they become routine and boring. It is a minuscule percentage of men/women who fearlessly get out of the steady/routine jobs and make a career of their own passion. If a couple is childless, they always feel the stress and heartbreak and also the feeling of being left out from the 'normal' group.
So we can see that there is always some or other form of pressure following every person throughout his life. If a person is of strong character, he will not bow down to the peer pressures and bring out unique personality in him. Peer pressure can have negative or positive impact depending on what kind of a person he or she is.