I was wondering. The tasks can communicate with themselves and with ISRs through queues. The same applies for co-routines.
The question that popped into my mind, how a co-routine and a task can communicate?

Read the first paragraph of http://www.freertos.org/taskandcr.html There is nothing to stop you using shared memory to pass information between the two.

In the header files of the co-routines, it says check the web page how a task can communicate with a co-routine.
There is nothing like that in the web pages.
By shared memory, you mean a global variable?
What about synchronization if it was the case?