If you plan to use Grid then you should download the selenium-server-standalone JAR file. All the components are available via selenium-server. The standalone JAR contains everything, including the remote Selenium server and the client-side bindings. This means that if you use the selenium-server-standalone jar in your project, you do not have to add selenium-java or a browser specific jar.
<dependency>
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-server</artifactId>
<version>3.X</version>
</dependency>