declare @mytable table (SNo int, Category varchar(100))
insert @mytable  
      select 1, 'XML/HTML'
union select 2, 'ASP.NET'
union select 3, 'C#'
union select 4, 'ASP.NET/C#'
union select 5, 'C#/XML'
union select 6, 'HTML/ASP.NET'
union select 7, 'SQL'
union select 8, 'SQL/HTML'
union select 9, 'SQL/XML'
union select 10, 'XML'
union select 11, 'C#'
union select 12, 'ASP.NET'
union select 13, 'SQL'
union select 14, 'XML'
union select 15, 'SQL'

select d.Item as Category, COUNT(*)  AS Count
from @mytable t
cross apply dbo.DelimitedSplit8K (Category, '/') d
group by d.Item

--Next time provide some DDL like so....

--1) Lets setup that test data
IF OBJECT_ID('tempdb..#classes') IS NOT NULL
		DROP TABLE #classes;

CREATE TABLE #classes (SNo int primary key, category varchar(20) NOT NULL);

INSERT INTO #classes
SELECT	1,'XML/HTML' UNION ALL
SELECT	2,'ASP.NET' UNION ALL
SELECT	3,'C#' UNION ALL
SELECT	4,'ASP.NET/C#' UNION ALL
SELECT	5,'C#/XML' UNION ALL
SELECT	6,'HTML/ASP.NET' UNION ALL
SELECT	7,'SQL' UNION ALL
SELECT	8,'SQL/HTML' UNION ALL
SELECT	9,'SQL/XML' UNION ALL
SELECT	10,'XML' UNION ALL
SELECT	11,'C#' UNION ALL
SELECT	12,'ASP.NET' UNION ALL
SELECT	13,'SQL' UNION ALL
SELECT	14,'XML' UNION ALL
SELECT	15,'SQL'

-- The query:
;WITH cat1 AS 
(	SELECT category FROM #classes WHERE CHARINDEX('/',category)=0),
cat2 AS
(	SELECT category FROM #classes WHERE CHARINDEX('/',category)<>0),
catall AS
(	SELECT category FROM cat1
	UNION ALL 
	SELECT SUBSTRING(Category,1,CHARINDEX('/',Category)-1) FROM cat2
	UNION ALL
	SELECT SUBSTRING(Category,CHARINDEX('/',Category)+1,LEN(category)) FROM cat2)
SELECT category, count(category) AS [count]
FROM catall
GROUP BY category

-- be nice to your dba
DROP TABLE #classes
GO

select d.Item as [Category], COUNT(*) AS Count
from @mytable t
cross apply dbo.fnSplit(t.[Category], '/') d
group by d.Item 

select D.Item as [Category], COUNT(*) AS Count
from dbo.TestCategory as T
cross apply 
(
select * from  dbo.fnSplit(T.[Category],'/') 
) as D
group by D.Item 

SELECT compatibility_level
FROM sys.databases WHERE name = 'database_name'