The biggest difference between fresh yeast and dry yeast is the different water content, which leads to different shelf life and usage.
Fresh yeast refers to the yeast with a moisture content of about 65% - 69%, which is directly squeezed from artificially cultivated yeast. Its shelf life is very short, only one month to 45 days, and it must be refrigerated throughout the whole process. It will quickly become inactive at room temperature and above.
As the name implies, dry yeast has a water content of only 4-6%, a long shelf life of about one year, and does not need to be refrigerated throughout. In addition, the use of dry yeast requires about 40 degrees of warm water, while the use of fresh yeast requires about 20 degrees of cold water, which is also due to the different use of water.