 Hello and welcome to the hands-on scientific computing course. I am Marijn van Vliet. And my name is Essie Heikinen and both of us work at Alder Scientific Computing. Which is a collection of experts on all things related to using computers for scientific research. In this course we aim to teach you all you need to know to use computers to manage, analyze and publish your data effectively. The course is for anyone who uses advanced computing and needs efficient solutions to solve problems. So it is not only for people in the academia. If you look at the course page you will see that there are many modules here that teach you different aspects of scientific computing. They are designed such that you can jump right into the module that seems to be the most useful to you. Or if you want to be thorough you can start at the beginning and go all the way through. The course was actually born out of the inspiration of teaching the skills that are often not taught directly in the classes. And organizing it into a structured guide. For example the course name refers to scientific computing but what does that even mean? Scientific computing and computer science are very close terms. But they refer to different approaches of computing. So to be clear computer science is more focused on information technology and algorithms. Whereas scientific computing is using a computer as a tool for science. Nowadays your computer behaves mostly like an appliance. It can be a typewriter or a video player or a game console. But in scientific computing we are using the computer as a really powerful calculator. So in a way we are going back to using a computer what it was originally meant for. To quickly do many calculations on a lot of data. Using a computer in this manner will sometimes be a little different than what you may be used to. To give you one example of a big difference usually we rely on the graphical user interface to operate our computer. There are buttons we can click and well-designed interfaces that guide us to accomplish our goal. However when you're doing science you probably are exploring new ideas and you want your computer to do things that nobody has ever done before. This means that there won't be a button that does exactly what you want. And this is why one of the things that we will be teaching you is the command line. In contrast to a GUI which presents you with a bunch of options the command line just sits there silently waiting for you to tell it what to do. You operate the computer by typing comments at it and when the comments become too cumbersome to type again and again you can write them down in a text file at which point you are writing actual computer programs. In this mode the computer presents itself more as a collection of CPUs and memory there to be used in any way you want. You will notice that you now have the whole potential of the computer at your disposal. All of this may sound like there's plenty of stuff to learn so that's why hands-on scientific computing was developed. To collect the essential pieces into an organized map so you get an overview of important resources for learning all of these topics. For example it's important that the code that you write produces the correct results. You don't want to have to retract the paper because you made a programming error and this is why we've included modules on model of code design and testing and debugging. In addition your science should be reproducible. Other people should be able to replicate your experiments and results and that is where using environments and writing documentation can be of help. Making sure that your code is correct and reproducible can be a lot of work and this is why we also cover tools that will make your life easier and save you tons of time. This includes things such as using the command line efficiently, virtual control and documentation generators. So go ahead and get started with the first module which aims to give you an overview of scientific computing and it will be a good jumping-off point to do the more advanced modules. If you want to know more about alto scientific computing you can visit psychomp.alto.fi to follow news, learn about computing at alto and find all of our upcoming workshops and courses. So good luck and have fun.