Most designers opt to use Adobe designer software - this provides them with a full suite of design tools to handle almost any project on DesignCrowd. That is:
Essentially downloading the Adobe Creative Suite 5: Design Premium (https://www.adobe.com/cfusion/tdrc/index.cfm?product=design_premium&promoid=FDTFM) gives a designer access to all design tools they need for any type of project.
If you are on a tight budget and don't want to spend too much money,there are some trial and free programs out there that are also used (notas much). See http://inkscape.org/
Note: On some projects, clients will request a particular format and therefore these require different software and output files. For example, clients may require designers to use Coral Draw (http://www.corel.com/
) and produce CDR output files.