Guru on Instagram: "#Arrays and Strings: Introduction to array, Processing Array Contents, passing array as argument. Returning array from methods, Array of objects, 2D arrays, Array with three or more dimensions, String class, String concatenation, Comparing strings, Substring, Difference between String and String buffer class, String Tokenizer Class. Interface and Packages: Basics of interface, Multiple Interfaces, Multiple Inheritance using Interfaces, Multilevel Interface, Packages, Create a