 So learners, last week we discussed how software is made up of several components and the process of creating a software. We looked at the example of the Amazon pay feature. So creation of such software systems begins with thinking about who is going to use the software for what purpose and in what way. Yes, after gathering the requirements from the end user, we need to create a design where the big picture of the software is developed. The actual creation of code happens after this which is often referred as the development phase. Following this is the testing and maintenance phase, but how do these activities happen? The nature of iteration in these activities are all captured in the software development process model. So learners, could you recollect some of the software development process models that were discussed, pause this video and write your answers in the notebook. So we saw that there are different software development models. We saw the V model, then there is the waterfall model and the agile process models to name a few. So the development team chooses a model that is appropriate for them. However, most of the times they adapt the model based on their own processes and also on the nature of the software that the team is developing. Okay, so let's try to apply the learnings from the different phases and models to an actual software design problem. The details of the problem are provided in the LXI.