RAM is the fastest storage memory which stores those files that are being accessed very quickly. Whenever a process requires those files, RAM send it to them at fastest speed without slowing the process down. If required files are not available in RAM then processor will require to fetch those files from hard disk which is the slowest storage unit. So, it will slow down the process due to additional time-lapse it adds.

More RAM space makes the process and overall system fast as it can then store more number of needed files. Hence, having more RAM increase the system performance whether it’s phone, tablet, laptop or personal computer.

In smartphones, RAM has very limited space and there are lots of task already running in background. So, you’re very limited about amount of apps you install or number of apps you runs simultaneously in your device. If you install many apps, open lots of apps or try to run heavy apps like high-end graphics games or software, it slows down your phone. Even proper optimization doesn’t help because your smartphone’s RAM (the hardware) limits its performance
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