For this module, I will be explaining to you the types of Construction Activities Relationship that we might face in any construction project that we deal with or work at. If you remember, in other module that's focusing on the activity on node, we highlighted that activity on node showing a graphical tool that shows a projects activities as rectangles or squares join by arrows including the relationship and the between these activities, as we can see here. So, from that side we mentioned that a node network diagram uses four types of construction activities relationship. From finish to start, from start to start, from finish to finish and start to finish or multiple relationship. So, what we discussed until today and most of the examples we gave was mostly focused on a situation in which the end of an activity is in necessary condition to begin a successor. For example, the end of activity B is necessary to begin activity D or F or S on another word, let's say activity E will not start until activity C finishes, this kind of relationship called the Finish to Start Relationship. And this also refers to as the traditional relationship, in a matter of fact most schedulers, they do prefer to only use this relationship when building their schedule. So, before I go deeper and dig deeper on the top of the relationships, I want to highlight something what we call the key. So for example, we have a construction activity of pouring a concrete. As we can see here we explain as a rectangle shape. You will noticed on your schedule and sometimes from softwares they developed the activity with something not just the name of the activity or the description of the activity but also more numbers in the rectangle that highlight more information about that specific activity. And before you read your schedule, you look for that key to highlight what are these numbers. So for example, I highlighted a quick example for you. If we have poor, incomplete activity, the description, what we usually put here is the name or describing of that activity. So that in this case would be pouring concrete. Activity ID is basically a number or that activity number in the list of activities you have in your project. And we covered that in the previous course on project initiation and planning. That refers what's we mean by the. And then, another number could be referring to the duration of that specific activity, could be in days, in weeks and months and then these four I highlighted here just I'm going to with them very quickly. One is the ES, refers to the early start of that activity, when that activity can start. The earliest possible time it will start. The same thing goes to EF which is when that activity that early finish time for that activity. The difference between the Early Start and the Early Finish, it's always has to be the duration of that activity. LS on the other hand, it refers to the latest start. What's the latest time that activity can start? And sometimes we mention that, or we need that number on what's the latest time an activity can start without affecting the project end date by any chance. This we will be talking about in much more details for other modules later on how to calculate all these numbers and why they are important. Last but not least we can have something called LF, for example which is the Late Finish. What's the latest time that the activity can finish without affecting the end date of the project to be shifted. Sometimes you might find more information below this rectangle, and other, maybe small, two rectangles or three highlighting the type of which we will also be discussing in a separate module in this course. So, I just want to highlight quickly what's the key before we dig deeper into the touch of the relationship, so as you can now relate in the examples that we will be giving you now in all of the times.
