Basically scalping is all about trading on very short timeframes. Scalpers usually hold position for just a couple of minutes. Consequently, a scalper usually makes 10-20 deals within a single trading session. There are certain pros and cons of this approach to trading.
As for pros, sclapers don't take huge risks during their deals. I mean that they trade with small lots, they set tight stop losses and take profits which helps them secure their risks. Another advantage of scaling, from my perspective is that they are always engaged in trading. So, they don't have the periods of doing nothing as they always follow the charts which gives them the total control over their opened deals.
However, I guess that scalping has more cons than pros. First of all, as I have mentioned the fact that scalpers don't take big risks within a single deal, they don't hope to get high profits. So, they can make 10-15 deals a day but they will earn no more than 100-200 pips a day. That looks depressing for me because you work a lot but don't get good profits. Another disadvantage of scalping is the fact that psychological aspect takes place in making decisions. Your psychology is affected by the market when you follow the charts all the time without any breaks. As they say, a trade starts to experience greed or fear and this affects the logic of the decisions. In addition to that, it is impossible to make a good analysis of the market for such a short time period. All the decisions are made in the fuss, that is why the probability of mistakes arises.
Surely, it is possible to earn good returns using scalping methods and some of the traders find such ultrashort trading to be the most preferrable way to make money out of trading. However, I find this tactics to be very exhausting and intimidating, but the tastes differ.