When would you use Auto CAD and when CATIA

For2D, we use AutoCAD.

For3D, we shall use CATIA / SolidWorks / SolidEdge / ProE / Inventor

CATIA is Very useful. It is one of the higher end products in a field called Parametric Modeling. Other, popular parametric modelers are SolidWorks, Pro-E, and Inventor. Learn the basics of parametric modeling, and you only need to learn the differences in the user interfaces of these.

They are used in mechanical design. CATIA is also capable of doing stress analysis. These softwares do not, however, think for you. To use them effectively you need to have some background in engineering.

only I use Autocad

Thanks for the invitation misses Woofter, I didnt know CATIA. What i see that they have more mechanical use. What I know of Autocad is that they specifically have software for all the disciplines of building. I honestly don know CATIA well enough to tell you when to use, but now I am triggered to get to know CATIA, thank you

CATIA V5-6R2014 delivers a number of usability and productivity enhancements such as thick profiles for cut-outs, user defined unfolded curve types, and offsets from a reference face. The new pattern of body” function allows sheet metal pattern features to be applied to the current solid

CATIA V5-6R2014 delivers new capabilities for the creation of complex joggle features on hydroformed parts. Users can now create the same joggle on a surfacic flange and its support (the web or another surfacic flange).  A surfacic flange can be created on another surfacic flange which contains joggles and a joggle can be created on a surfacic web

simple Auto Cad is for2-D drawing

Catia has both2D and3D but mostly is used for3D and also for creating complicated parts/objects

I am using Autocad for2D drafting only..CATIA for3D designing, but  am not Using.

I only use Autocad .. It's used more than any other software in my country .. thanks 

Thanks for Invitation Elke,

I am Using AutoCAD because most the work in2 Dimensional. But as per my Knowledge

Use of AutoCAD is good when any drafter, Architect, Engineer, or use in any industry for developing of2 dimensional Drawings, including all drawings i.e. concept drawing, schematic drawings, shop drawings, working drawings, as built drawings, submission drawings, and so many….. but most of the use is2D because the CAD supported3dimensional but not fully equipped and  time consuming.

Use of CATIA is the best for any drafter, designer, Engineer, or any other industry but the most power full for Mechanical engineering. We can create3 dimensional very easy and time saving. CATIA is enables the creation of3D parts, from3D sketches, molded, forged or tooling parts up to the definition of mechanical assemblies. CATIA also provide the advanced technologies for mechanical surfacing and BIW and a wide range of applications for tooling design, for both generic tooling and mold & die. CATIA offers a solution to shape design, styling, surfacing workflow and visualization to create, modify, and validate complex innovative shapes from industrial design to Class-A surfacing with the ICEM surfacing technologies.