I am currently an eighth grader but I have a deep interest in ARM processors, since I'm a neophyte but I have great interest could u tell me what makes ARM processors so significant? Why? Thank you :)

There are two main reasons why I firmly believe that ARM processors are here to stay and should be considered first after getting your project requirements.

First, it is clearly the number 1 processor deployed to the market, so if you know ARM architecture you can say you know the most important processor architecture for most of the jobs today. Below I quote wikipedia so you see what I am talking about:

"Globally ARM is the most widely used instruction set architecture in terms of quantity produced^. The low power consumption of ARM processors has made them very popular: over 50 billion ARM processors have been produced as of 2014, of which 10 billion were produced in 2013^] and "ARM-based chips are found in nearly 60 percent of the world’s mobile devices". The ARM architecture (32-bit) is the most widely used architecture in mobile devices, and most popular 32-bit one in embedded systems. In 2005, about 98% of all mobile phones sold used at least one ARM processor. According to ARM Holdings, in 2010 alone, producers of chips based on ARM architectures reported shipments of 6.1 billion ARM-based processors, representing 95% of smartphones, 35% of digital televisions and set-top boxes and 10% of mobile computers."

Second, The amount of existent resources for it is amazing, there are virtually every tool you need for designing, implementing and debugging for free out there (open source) so you can really prototype in a constrained budget. At least to the point of getting a proof-of-concept for your project and that way convince your client that the solution works.

There are two main reasons why I firmly believe that ARM processors are here to stay and should be considered first after getting your project requirements.

First, it is clearly the number 1 processor deployed to the market, so if you know ARM architecture you can say you know the most important processor architecture for most of the jobs today. Below I quote wikipedia so you see what I am talking about:

"Globally ARM is the most widely used instruction set architecture in terms of quantity produced^. The low power consumption of ARM processors has made them very popular: over 50 billion ARM processors have been produced as of 2014, of which 10 billion were produced in 2013^] and "ARM-based chips are found in nearly 60 percent of the world’s mobile devices". The ARM architecture (32-bit) is the most widely used architecture in mobile devices, and most popular 32-bit one in embedded systems. In 2005, about 98% of all mobile phones sold used at least one ARM processor. According to ARM Holdings, in 2010 alone, producers of chips based on ARM architectures reported shipments of 6.1 billion ARM-based processors, representing 95% of smartphones, 35% of digital televisions and set-top boxes and 10% of mobile computers."

Second, The amount of existent resources for it is amazing, there are virtually every tool you need for designing, implementing and debugging for free out there (open source) so you can really prototype in a constrained budget. At least to the point of getting a proof-of-concept for your project and that way convince your client that the solution works.

About the first part (market share): it's more of a consequence than a reason. :-)

The second part - well, that's a chicken-egg problem (or snowball-effect).

I guess the main thing is: good bang for a buck - in its application area.

Not good for small systems or big systems, but excellent in the middle.