Live coding or on-the-fly programming, also just in time programming and conversational programming — an approach, when one developer writes code and the others supervise it in real time. 

In our company we use coding most often in the recruitment process. During the interview we ask the candidate to solve an algorithmic problem, such as finding the intersection of two arrays. Thanks to live coding, we can trace how a person thinks and what approaches to solving problems he or she uses. Based on this we can conclude, what practical base knowledge the candidate has. 

Live coding — an excellent indicator of the ability to solve problems in real time. But, there is a downside — it takes too much time and can be quite stressful for the candidate. 

Besides during the recruitment process, live coding is also used in the process of studying, when a more experienced developer shares his or her approach with juniors.