There are two key things in defects of the software testing
1) Severity
2) Priority

What is the difference between Severity and Priority?

𝗦𝗲𝘃𝗲𝗿𝗶𝘁𝘆:
The impact of the bug/defect on the application is known as the severity. It is the extent to which the defect can affect the software. In other words, it defines the impact that a given defect has on the system.

Types of Severity
There are four different levels of severity.
1.    Critical
2.    Major
3.    Minor
4.    Low

📌 Critical
A defect that completely blocks the testing of the product/feature is a critical defect. If the application crashes or becomes unusable/not able to proceed further, the defect could be classified under critical severity.

📌 Major
Any Major feature implemented that is not meeting the customer’s requirements/use case(s) and behaves differently than expected, can be classified under Major Severity.

📌 Minor
A medium defect appears when the product or application doesn’t meet certain criteria or still exhibits some strange behaviors, however, the functionality as a whole is not impacted and can be classified under Minor Severity.

📌 Low
Any corrective defects including spelling mistakes or alignment issues or font casing can be classified under Low Severity.

𝗣𝗿𝗶𝗼𝗿𝗶𝘁𝘆:
Priority of a defect is related to how quickly a bug should be fixed and deployed to live servers. When a defect is of high severity, most likely it will also have a high priority.
The higher the priority the sooner the defect should be resolved.
Likewise, a low-severity defect will normally have a low priority as well.

📌 Low: 
The defect is an irritant that should be repaired, but repair can be deferred until after more serious defects have been fixed.

📌 Medium: The defect should be resolved in the normal development activities. It can wait until a new build or version is created.

📌 High: The defect must be resolved as soon as possible because the defect is affecting the application or the product severely. The system cannot be used until the repair has been done.

Below are the examples for different combinations of priority and severity
1.    𝗟𝗼𝘄 𝗽𝗿𝗶𝗼𝗿𝗶𝘁𝘆-𝗟𝗼𝘄 𝘀𝗲𝘃𝗲𝗿𝗶𝘁𝘆 – A spelling mistake in a page not frequently navigated by users.
2.    𝗟𝗼𝘄 𝗽𝗿𝗶𝗼𝗿𝗶𝘁𝘆-𝗛𝗶𝗴𝗵 𝘀𝗲𝘃𝗲𝗿𝗶𝘁𝘆 – Application crashing in some very corner case.
3.    𝗛𝗶𝗴𝗵 𝗽𝗿𝗶𝗼𝗿𝗶𝘁𝘆-𝗟𝗼𝘄 𝘀𝗲𝘃𝗲𝗿𝗶𝘁𝘆 – Slight change in logo color or spelling mistake in the company name.
4.    𝗛𝗶𝗴𝗵 𝗽𝗿𝗶𝗼𝗿𝗶𝘁𝘆-𝗛𝗶𝗴𝗵 𝘀𝗲𝘃𝗲𝗿𝗶𝘁𝘆 – Issue with login functionality.

Omer Khan