documentclass
Documentclass is a core LaTeX command used to specify the overall class and formatting rules for a document. The command has the form \documentclass[options]{class} and must appear as the first non-comment line in a LaTeX source file, before \begin{document}. The class file (.cls) defines the document’s structure, default typography, available sectioning commands, and other formatting conventions for that class.
Commonly used classes include article, report, book, and letter, with beamer used for presentations. Each class
Options passed to documentclass control broad aspects of layout and typography. Typical options include font size
In practice, authors select a class at the start of the document, then load additional packages in