Every computer language has data types: strings, numbers, symbols, and so on. But every language handles them differently, this is called typing. In languages like Java it is static: if you type a numeric variable, you first have to type it. The computer looks at the type and knows: this is going to be math.
But it’s safer this way – the language protects the programmer from his own mistakes. Don’t compare bananas with numbers!
The magic of the Java language is in its virtual machine (JVM). The virtual machine allows you to run the code on any device where it is installed. If the machine can be started, the program will be started. This makes it easy to write software in Java for many different devices: servers, computers, smart phones, ATMs and even robots.
What is easier to learn
In the beginning, you’ll sweat in Java, but later you’ll be able to run complex systems. It’s also easy to switch from Java to other languages – Kotlin or C#.