The meaning of the statement are almost similar to what it sounds:-
System.setProperty("webdriver.chrome.driver","path to chromedriver.exe");
// This basically sets the system property to value named webdriver.chrome.driver and the path is mentioned to get the chrome driver
Webdriver driver = new ChromeDriver();
// This is basically used to create an instance of the chrome driver.
Hope you got the meaning of the statements.
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