Thank you. You answered my question.
Ultimately, I was wondering about what are the fundamental data structures in R. In Python, for example, we have elementary data types, lists, dictionaries, tuples, and a few others. In Wickham's book, he distinguishes between 5 structures (vectors, matrices, arrays, lists, data frames), yet he did not mention tables here, and I was wondering how the fitted in to the data structure types of R.