Difference between Session/processes/thread/worker/request etc

Hi ,

Please help me in the understanding of following and their relationship with each other.

a)Select count(*) from sys.sysprocesses-- 35
b) Select count(*) from sys.dm_exec_sessions--35
c) --Select count(*) from sys.sysprocesses where spid > 50 --4
d) Select count(*) from sys.dm_exec_requests--32
e) select count(*) from sys.dm_os_tasks--49
f) select count(*) from sys.dm_os_workers--51
g) select count(*) from sys.dm_os_threads--60
h) select count(*) from sys.dm_os_schedulers--11, Visibal Online =4 (Excluding DAC)

Should I conclude below

(a) and (b) is same thing , if I am looking for number of sessions connected.

There are 4 User sessions, concluded from (C).

only 32 are actively doing something , concluded from (D).

These 32 active requests have been running on 4 core/schedulers (h) as 49 tasks(e).

An example will be appreciated.

Thanks Aslam