struggling to understand Random class constructor with one parameter of long type [duplicate]

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• What is the use of the Random(long) constructor? 4 answers

I'm relatively new to java and is studying the random class in java se8. I'm struggling to understand the random class constructor with one parameter of type long. I have attached a screen shot of the explanation in java documentation, bt I'm really struggling to understand what it actually means. Could someone please kindly explain it to me in a way that's easier to understand? Thanks in advance for any help!