Abbreviations

Acronyms via \gls: the long form on first use, the short form afterwards, plus an auto-built list.

Example
Definitions
Preamble

$Rendered LaTeX output$

At the first pass, the \gls{er} was 5.
At the second pass was \gls{er} 3.
The plural form can be seen here: \glspl{er}.
To demonstrate what the list of abbreviations looks like for longer description texts, \glspl{rdbms} must be mentioned here.

\gls{dante} is a local \TeX\ user group.
The German-speaking local \TeX\ user group is \gls{dante}.
A \gls{gp} is a medical doctor.
I went to my surgery to see the \gls{gp}.

% Note the difference between "acronym" and "abbreviation": https://english.stackexchange.com/q/3755/66058
% We regard abbreviation as superset of acronym
% `er` is used by the English example, `fr` by the German one. Both are defined in
% both abbreviation lists because the template ships a single abbreviations.tex that
% every main file (English and German) loads -- an undefined entry breaks the build.
\newabbreviation{er}{ER}{error rate}
\newabbreviation{fr}{FR}{Fehlerrate}
\newabbreviation[shortplural={RDBMS},longplural={RDBMS}]{rdbms}{RDBMS}{Relational Database Management System}
\newabbreviation[category=abbreviationdot]{dante}{DANTE e.V.}{Deutschsprachige Anwendervereinigung \TeX\ e.V.}
\newabbreviation{gp}{G.P.}{General Practitioner}

% Source: https://tex.stackexchange.com/a/154566/9075
\newabbreviation{html}{HTML}{hypertext markup language}
\newacronym{nato}{NATO}{North Atlantic Treaty Organization}

\usepackage[
  translate=babel,
  abbreviations,         % create "abbreviations" glossary
  nomain,                % don't create "main" glossary
  stylemods=longbooktabs % do the adjustments for the longbooktabs styles
]{glossaries-extra}
\setglossarystyle{long3col-booktabs}

% Hint by https://tex.stackexchange.com/a/463188/9075
% \usepackage{glossary-longextra}

% Following is required if the abbreviation list should be sorted automatically (\printglossary / \printglossaries)
% Not required, if we printed the entries in-order (using \printunsrtglossaries)
% Required to have the German chapter name % Source: https://tex.stackexchange.com/a/426392/9075
\makeglossaries

\input{abbreviations}