Paragraphs and new lines

\documentclass{article}
\begin{document}

This is the first paragraph. It can span multiple lines in your source file, but LaTeX will format it as one continuous paragraph in the output.

This is the second paragraph. Notice the blank line above - that's what tells LaTeX to start a new paragraph. LaTeX automatically indents the first line.

\end{document}

This    has    multiple    spaces.
This is on
multiple lines
in the source.

This is a new paragraph.

\documentclass{article}
\begin{document}

First line\\
Second line\\
Third line

This is still the same paragraph, but with forced line breaks.

This is a new paragraph.

\end{document}

First line\\[10pt]
Second line with 10pt gap\\[0.5cm]
Third line with 0.5cm gap

Normal line break:\\
Next line

% Prevent breaks in names
Dr.~Smith wrote Chapter~5.

% Keep units together  
The temperature is 25~°C.

% Prevent awkward breaks
See Figure~\ref{fig:example} on page~\pageref{fig:example}.

\documentclass{article}

% Remove indentation globally
\setlength{\parindent}{0pt}

% Or set custom indentation
% \setlength{\parindent}{1cm}

\begin{document}

This paragraph has no indentation because we set parindent to 0pt.

This paragraph also has no indentation. All paragraphs follow the global setting.

\indent This paragraph is manually indented using the indent command.

\noindent This paragraph has no indentation even if parindent is set.

\end{document}

\documentclass{article}

% Add space between paragraphs
\setlength{\parskip}{1em}

% Remove indent when using parskip
\setlength{\parindent}{0pt}

\begin{document}

First paragraph with spacing after it.

Second paragraph with spacing before and after it.

Third paragraph.

\end{document}

\begin{center}
This text is centered.\\
Multiple lines\\
can be centered.
\end{center}

% Or for short text:
{\centering This is also centered.\par}

\begin{flushleft}
This text is\\
aligned to\\
the left.
\end{flushleft}

\begin{flushright}
This text is\\
aligned to\\
the right.
\end{flushright}

% Prevent hyphenation for specific words
\hyphenation{LaTeX JavaScript Python}

% Prevent hyphenation in a word
\mbox{unbreakableword}

% Allow hyphenation at specific points
super\-cali\-fragi\-listic

John Smith\\
123 Main Street\\
Anytown, ST 12345\\
USA

\begin{verse}
Roses are red,\\
Violets are blue,\\
LaTeX is awesome,\\
And so are you!
\end{verse}

\begin{quote}
This is a short quotation. It's indented from both margins and has no paragraph indentation.
\end{quote}

\begin{quotation}
This is a longer quotation that might span multiple paragraphs. The first line of each paragraph is indented.

This is the second paragraph of the quotation.
\end{quotation}