After installing SQL Server, you will discover a folder with a number of files under your program files. Any number, such as 80, 90, 100, 110, 120, 130, 140, 150, or 160, may be used in the folder names. This truly corresponds to the current version of SQL Server, and in this post, you can see which number corresponds to which version.
Here is the mapping list:
80 = SQL Server 2000 = 8.00.xxxx
90 = SQL Server 2005 = 9.00.xxxx
100 = SQL Server 2008 = 10.00.xxxx
105 = SQL Server 2008 R2 = 10.50.xxxx
110 = SQL Server 2012 = 11.00.xxxx
120 = SQL Server 2014 = 12.00.xxxx
130 = SQL Server 2016 = 13.00.xxxx
140 = SQL Server 2017 = 14.00.xxxx
150 = SQL Server 2019 = 15.00.xxxx
160 = SQL Server 2022 = 16.00.xxxx
The older versions are displayed since I previously had different SQL Server instances. Despite having all these Identifiers on my machine, I may not actually have all the instances. Some were long ago uninstalled, but the directories were left in place. Since I decided to have backward compatibility when installing the SQL Server, some Identifiers were added. Some identifiers were created by SSDT or Visual Studio since I use SQL Server data tools to build reports for SSRS.