An Operating system is a software that allows an interface between the hardware and software of a device. It acts as a bridge of communication between the user command and the hardware.
You may be running multiple programs at a time. Each program need to access the CPU, memory and storage. OS takes care of these process. It makes sure that every program gets what it needs and runs smoothly.
Each Operating System is defined by its own looks and design which is named as User Interface (UI). The UI is the one which is felt by the user. We use the interface to give command to the software, which then makes the relevant hardware to perform.
Some devices are made to perform the command given only by specified OS. While others can adopt few upgrades and can be made to run on different software OS.
In short, they allow you to communicate with your device without knowing how to speak a machine language.
2G | 3G | 4G | Accelerometer | Battery Type | Bluetooth | CPU | Color Reproduction | Dimension | Display Size | Display Type | Expandable Memory | Front Camera | Fingerprint Sensor | GPU | GPS | Gyroscope | InfraRed | Internal Memory | Iris Scanner | NFC | Primary Camera | Pixel Density | Proximity | RAM | Resolution | SIM | System Chip | Screen to body Ratio | Touchscreen type | USB | Video FPS | Wi-Fi