Create a static box in LaTeX

Question

How can I make a command to automate the creation of a box? This box would enclose texts or statements, questions and the like when the command is used. Example:

Answer 1

Using tikz, mdframed, \fbox and \framebox:

\documentclass{article}
\usepackage{tikz}
\usepackage[framemethod=default]{mdframed}
\newcommand{\mybox}[1]{%
\begin{tikzpicture}
\node[draw,rectangle,rounded corners=4pt,line width =1.5pt,text width=5cm,minimum width=5cm,minimum height=3cm]{#1};
\end{tikzpicture}
}
\newcommand{\myboxmd}[1]{%
\begin{mdframed}[linewidth=1.5pt]
#1\par
\end{mdframed}
}
\setlength{\fboxrule}{1.5pt}
\newcommand{\myboxframe}[1]{%
\framebox[.5\textwidth][t]{#1}
}
\begin{document}
\noindent
\mybox{Text is placed here}
\par\noindent
\myboxmd{Text is placed here}
\par
\noindent
\myboxframe{Text is placed here}
\par
\noindent
\fbox{Text is placed here}
\end{document}