# Difference between a space and a “wave” symbol (tilde/“~”)?

As title, what is the difference between a and ~?

I see no differences after the compilation.

MWE:

\documentclass[a4paper]{article}

\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage[colorinlistoftodos]{todonotes}

\author{You}

\date{\today}

\begin{document}
\maketitle

I am cool.

I~am~cool.

\end{document}

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You will see the difference at end of line. ~ is unbreakable space where as space isn't unbreakable. –  Harish Kumar Mar 28 at 1:54
"I am cool"... That's a rather bold statement :p –  Jubobs Mar 28 at 2:23

The difference can be seen at the end of line. A space is breakable and a ~ is an un-breakable space.

\documentclass[a4paper]{article}

\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage[colorinlistoftodos]{todonotes}

\author{You}

\date{\today}

\begin{document}
\maketitle

\hspace*{0.9\textwidth}I am cool.

\hspace*{0.9\textwidth}I~am~cool.

\end{document}


The three words I am and cool are glued together in the second line.

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