abbreviations/acronyms via the acro package in latex

The best package for acronyms in latex documents is

\usepackage{acro}

To define acronyms you use the following commands:

\DeclareAcronym{command}{short=shortform,long=longform}

You can use the acronyms in a text via

\ac{command}

changing \ac into

\Ac     -capital initial
\acp   -plural
\ac*    -without marking it as already present
\acl     - long form
\acs    - short form

for follow reading:

http://mirror.unl.edu/ctan/macros/latex/contrib/acro/acro_en.pdf