Diantokam: Program

PDFArchitect

PDFArchitect is a tool to easily modify your PDF files - i.e. you can merge two files, delete pages or rotate them.

Source : http://download.pdfforge.org/download/pdfarchitect

PDFCreator

PDFCreator allows you to easily create PDF files from any Windows program. Use it like a printer in Word, StarCalc or any other Windows application.

Source : http://download.pdfforge.org/download/pdfcreator

Images2PDF

Images2PDF is the easy and fast way to convert images to pdf files. You can import different image file types, set different output formats und export all as a pdf file.

Source : http://download.pdfforge.org/download/images2pdf

DraftSight is a proprietary freeware 2D CAD (computer-aided design or computer-aided drafting) product for engineers, architects, designers, draftspeople, students and educators. The product was developed by Dassault Systèmes and lets users create, edit and view DWG and DXF files.

DraftSight competes against more than three dozen 2D or 2D/3D hybrid products on the market. General availability of DraftSight for Windows was released in February 2011 and was downloaded more than 1.8 million times as of December 2011.

Screenshot

Source : http://en.wikipedia.org/wiki/DraftSight

LibreCAD

What is LibreCAD

LibreCAD is a free Open Source CAD application for Windows, Apple and Linux. Support and documentation is free from our large, dedicated community of users, contributors and developers. You, too, can also get involved!

Quick Links:

Wiki : http://wiki.librecad.org

Forum : http://librecad.org/cms/home/get-help/forum.html

Blog : http://blog.librecad.org/

Code Repository : https://github.com/LibreCAD/LibreCAD

Video Tutorials: http://www.youtube.com/results?search_query=librecad(Big thanks to the tutorial authors)

LibreCAD is a fully comprehensive 2D CAD application that you can download and install for free. There is a large base of satisfied LibreCAD users worldwide, and it is available in more than 20 languages and for all major operating systems, including Microsoft Windows, Mac OS X and Linux (Debian, Ubuntu, Fedora, Mandriva, Suse ...).

You can download, install and distribute LibreCAD freely, with no fear of copyright infringement.

LibreCAD's features

LibreCAD is a feature-packed and mature 2D-CAD application with some really great advantages:

It's free – no worry about license costs or annual fees.
No language barriers – it's available in a large number of languages, with more being added continually.
GPLv2 public license – you can use it, customize it, hack it and copy it with free user support and developer support from our active worldwide community and our experienced developer team.
LibreCAD is an Open Source community-driven project: development is open to new talent and new ideas, and our software is tested and used daily by a large and devoted user community; you, too, can get involved and influence its future development.