Bug identification is a significant aspect of the software development cycle. The bugs often get identified by the testers or the end user, but who identifies them makes a big difference. Depending on who encountered the bug and at which level decides which attribute gets associated with it. The two attributes used to signify these bugs are severity and priority. Severity is the impact a bug has on the development or operational phase of a component. The testing lead decides the severity or degree of the bug's impact after checking how it can affect the product functionalities and operations. Bug severity gets categorized into the following types: Critical It is the bug due to which the software has stopped working abruptly. Whether the tester has reached a level where he cannot execute any test operation or the user cannot use any product functionality. These bugs are critical as they need to get fixed immediately for the product to operate well. Minor It is a level where functionality is fine, but the desired standards do not get met. For example, the software operations are working fine, but the user interface needs a change. There is enough time to deal with these bugs, as there is no urgency. Major It is when some parts of a few functionalities are not up to the mark, but the software has not stopped working. It is a critical issue but not significant enough to be dealt with immediately. Low The valid yet harmless defects like spelling mistakes fall under the low severity category. You can fix them as and when without any urgency. If you face a severe bug, it is urgent to fix it before it damages the product or earns a poor reputation for the organization. That is where the concept of priority comes into existence. Priority defines how urgently or how soon you need to fix the bug. It can vary for different products, depending on the bug you identify. Hence, it is a subjective aspect, and it gets categorized as follows: High These bugs are urgent and need to get fixed on priority. High priority means the time you have for resolving them is low, and the designated team should act upon it at once. Medium The defects that have no direct impact on the business fall under the medium priority. The team need to fix them soon, but not as soon as the high-priority defects. Low These are the defects that are of the least priority. It means you can take as much time as you want to fix them as they do not cause any significant damage to the software or the user. These are the bug priority categories, and a tester decides in which category the defect falls to find a solution for it. For better clarity, refer to the differences mentioned in the table below. Severity Priority Defines the impact on the functionality of the application under question. Defines the impact on the business or revenue of the firm using the application. The testing team decides the category of severity aspect. The end user or the client decides the priority category of a bug. The focus is on the technical aspects of the application. The focus is on the timeframe required to fix the detected flaw. It is not subjective. The value may vary with time. The value of a priority may change with time or after you compare the defect with others you may have found.