So, I have been reading about threads, handlers and other stuff .
(Small spoiler alert: I am not very good in Operating system’s working even though I had this subject last semester)
Although my main aim is to get a rough understanding of handlers and stuff, so I can go back to understand camera apis, please let me know if I have to work more on my basics first:

from what I have read on developers site, and so so many different sites, here is what I have understood (ps: correct me if am wrong, hehe):

- Process is the the code in execution. A process can have many threads, but each process has atleast 1 thread.
- Threads are just blocks of individual executable codes.
- The characterstic  property of threads are that threads are completely independent of each other’s  resources. 
–for eg if ui thread has buttons and stuff, then another thread can’t access those buttons or change some textview’s text 
-Another characterstic property of thread is they  follow a lifecycle with various stages of start, running,wait, dead , etc . basically, this : https://www.tutorialspoint.com/java/images/Thread_Life_Cycle.jpg  . In this lifecycle, its clear that a running thread will either go into wait state or dead state, and thus cannot be re used. 
- Thus, we have to make a thread like ui thread run for infinite time unless explicitley stopped. So the android uses handler and looper for ui thread.
- I imagined the system like this : https://imgur.com/ufLizqk  looper of a thread is like a big loop in which processor gets stuck. The thread is not getting executed ‘completely’ as long as looper is running. Handler is like a modem, it can take task of the current thread and pass it in looper, where
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