Learning how to brew better beer involves learning not only the abstract concepts, but the practical details of how things work in your brewery. One of the best ways to find out how your system works and have a repository of this information is to keep a brewing notebook. A brewing notebook is not just a place to store all your recipes — if you take detailed notes on your brewdays, it will contain a wealth of information. This information will allow you to check on information from prior beers. In addition, and perhaps more importantly, it can help you plan your future brew days and make future brewdays run more smoothly. In general, there should be a point to every measurement you record. On the other hand, measuring and recording various things during your brewday doesn’t take long and may be useful later. Here are some of the things you can record in your brewing notebook and how they can help you.