:orphan:
# MPI_Comm
the basic object used by MPI to determine which processes are involved in a communication
## Note
This manual page is a place-holder because MPICH does not have a manual page for `MPI_Comm`
## See Also
`PETSC_COMM_WORLD`, `PETSC_COMM_SELF`
## Level
beginner
## Location
include/petscsys.h
## Examples
src/ksp/ksp/tutorials/ex65.c
src/ksp/ksp/tutorials/ex74.c
src/snes/tutorials/ex15.c
src/sys/classes/random/tutorials/ex2.c
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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/include/petscsys.h)
[Index of all Sys routines](index.md)
[Table of Contents for all manual pages](/manualpages/index.md)
[Index of all manual pages](/manualpages/singleindex.md)