\documentclass{article}

\usepackage[acronym]{glossaries}  % provides support for glossaries and acronyms
\makeglossaries
\newacronym{ft}{FT}{Fourier transform}

\begin{document}

This is some text about \acrfull{ft}. And again we mention \gls{ft}, but really
we like \gls{ft}.

\printglossaries

\end{document}
