In LATEX input, words are separated by spaces, and paragraphs are separated by blank lines. However, adding extra spaces will not increase the space between words in the output, and adding extra blank lines will not increase the space between paragraphs. Spaces at the beginning of a paragraph are ignored--paragraph indentation is inserted automatically whether there are spaces in the input or not.
There are commands that you can use to insert extra space
in the output. To insert some extra vertical space, for example
between paragraphs, use the commands \smallskip,
\medskip, and \bigskip. There is a \medskip
just before this paragraph, so you can get an idea of the size.
You can insert a specific amount of vertical space with a
command such as \vskip{0.5 in}
The units of measurement--which can be in for inches, cm for
centimeters, or pt for points--must be specified.
If you would like to leave out the indentation at the
beginning of a particular paragraph, put the command
\noindent at the beginning of the paragraph.
You can insert horizontal space with \hspace, which
works similarly to \vspace. The commands
\quad and \qquad also insert horizontal
space. (``Quad'' is a printer's term; qquad is a double quad.)
LATEX also ignores line breaks inside paragraphs. The text
in the paragraph is automatically broken into lines in an optimal
way. LATEX even breaks words and inserts hyphens if necessary.
However, you can force a line break by typing the command \\.
This command works almost anywhere. For example, you can use
it in the title of the document, even though that is not
an ordinary paragraph.
Sometimes, you want to tell LATEX not to break a
line at a certain space. For this, you can use the
~ character as a non-breaking space. The
~ does not appear in the output--it becomes a space.
However, LATEX will definitely avoid breaking the line at
that space.