Why is synchronisation between different processes belonging to the same or different programs is an important task in parallel computing?

This is a complex topic in computer science ...

 

Parallel systems need synchronization, the def of sync is 'equilibrium enforcement', sync differs depending on what are you synchronizing,

 

I will give a simple examples:

 

1. Sync Send: The sender has to wait until, data is received

 

2. Sync Receive: The receiver waits until data comes

 

3. Sync Time: All entities reset their clocks as coordinated

 

4. Sync DataBases: All DataBases stop query processing, until all data are distributed to all

 

5. Sync Data Between N Data Storages: data on one side are generalized in other sections, shared data checked, and modified data are versioned* and data set according to priority\timestamp

 

.. as I said before, this is a complex topic in computer science

 

good luck,