Latest advice on the euro symbol

Question

I know there are many packages that offer the euro symbol (€). But which is the best implementation? I read something a couple of years ago [which I can't now find] that assessed the option. But even if I could find it, I imagine things might have changed since it was written. So: which package provides the best euro symbol (in terms of accuracy to the official specifications, in terms of looking good with the surrounding font and so on.) In response to Thorsten Donig's answer I should point out that these two desiderata seem in pretty much direct conflict if you're using a serif font.

The unicode symbol € doesn't work. (If you have a "compose key" it's "c=")

Answer 1

The unicode symbol € does work, if you use a modern font that contains that symbol. :-)

The best practice is to use right symbol for right font. For Computer Modern fonts, eurosym is OK, or textcomp (using fonts provided by CM-super). See this FAQ for more packages:

https://texfaq.org/FAQ-euro

I suggest Latin Modern fonts (using lmodern together with textcomp package), which is similar to Computer Modern. So you can use:

\documentclass{article}
\usepackage[utf8x]{inputenc}
\usepackage{lmodern,textcomp}
\begin{document}
€100
\end{document}

There are still some other font packages with euro symbol. If you use such font themes, use the euro symbol provided by the font package. For example, libertine, fourier and mathdesign package. Thus you can also use:

\documentclass{article}
\usepackage[utf8x]{inputenc}
\usepackage{libertine} % or \usepackage{fourier} or \usepackage[utopia]{mathdesign}
\begin{document}
€100 % or \texteuro100
\end{document}

Using XeLaTeX, most modern OpenType/TrueType fonts have euro symbols, including default Latin Modern fonts. You can use them directly:

% xelatex
\documentclass{article}
\usepackage{fontspec}% Latin Modern by default
% or \setmainfont{Whatever you want}
\begin{document}
€100
\end{document}

Answer 2

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{textcomp}
\usepackage{eurosym}

\begin{document}

10€ and 10\euro

\let\texteuro\euro
10€ and 10\euro

\end{document} 

Answer 3

The eurosym package is the one and only that translates the official specifications.