My latex file is:
\title{\large\textbf{Optimizarea rela\c tiei dintre structur\u a \c si comportament \^in modelarea UML}}
\author{
Sorin Oltean \\
\textit{Universitatea Transilvania din Bra\c sov} \\
\small\textit{oltean.s@gmail.com, sorin.oltean@romtelecom.ro} \\
\small Tel.: 0752/314288
}
\documentclass[12pt]{article}
\begin{document}
\maketitle
\renewcommand\abstractname{\textit{\textbf{Abstract}}}
\begin{abstract}
Something..... text.........
\end{abstract}\\\
\textbf{Cuvinte cheie:} \textit{sistem, structur\u a, comportament, UML}
\section{Introducere}
\paragraph{ }
Para11.............
\paragraph{ }
Para2......
\bibliographystyle{abbrv}
\bibliography{main}
\end{document}
After para1, I want to start a new paragraph, but between the paragraphs there is a blank line. How can I start the second paragraph below the first one, without that blank space?
Also, how can I define the margins (top, down, left, right) of the document? There is too much space from the left, right, top, and down, I want just 2cm space from the left and right, and 3cm from the top and down.
Also how can I specify the font name and size of the document?
Use the geometry package. It allows full control over margins etc.
\usepackage{geometry}
\geometry{margin=2cm}
The space between paragraphs can be set via parskip:
\setlength{\parskip}{0cm}
However, parskip does not work for paragarphs introduced by \paragraph. But if your paragraphs do not need a caption (as I assume since you wrote \paragraph{}, it may be better to begin paragraphs just with a blank line:
\setlength{\parskip}{0cm}
Here goes the first paragraph.
Here the second. With no space. Note that this paragraph was introduced with a blank line.
\paragraph{The third paragraph} This paragraph will have a small offset, since it is introduced explicitly with paragraph command.