Computer Aided Design :

Computer Aided Design also known as CAD for short.

- Computer Aided Design is the use of the computer to design objects for production or manufacture, such as houses, cars, boats and electronic circuits.

- CAD allows professionals such as engineers and draftsmen to produce complex drawings quickly and easily.
FEATURES :

1. CAD provides interactive drawing tools which means there is immediate response to input direct communication between users and computers.

2. CAD provides 2-D, 3-D and even (12, 14, 16-D) dimensional drawings.

3. A scale model allows user to see any angle from any different view.

ADVANTAGE OF USING CAD :
1) CAD save time.

2) A figure can be easily rotated, modified, copied, scaled (enlarged or reduced) and reflected.

3) CAD generated drawings are far better than manual drawings.

4) It is possible to present the drawing from different angles and in different sizes without redrawing.
APPLICATION OF CAD :
1) Building models : car, earoplane and goods manufacturers use CAD extensively to build 2-D or 3-D models.

2) Computer Aided Manufacturing : a computer directs the machines to make a products. The product to be made would have to be designed by using a CAD program. Both CAD and CAM are automating the manufacturing process. by using both application, its make production cheaper.

advantages and disadvantages of the written and off-shelf software :

advantages for the Written / Custom software :

1. You have the whole right to the software as it was created for you.
2. The software can be edited over and over again if there were problems arises.
3. The software can also be used to combined the features from other packages with the features that the company needs.
4. Not to forget, it is very expensive to in term of prices.


disadvantages for the Written / Custom software :

1. It is actually expensive to hire programmers to design the software.
2. the programmers must have a very good skill and expert to fulfill the company needs.
3. it also takes a lot of time to finish the software.

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advantages for the Off-Shelf software :

1. It is suitable for everybody to use the software.
2. Their documentation is easy to undersatnd and it is tested before being sold. So the software is user friendly and easy to use.
3. It is cheaper since no need to hire any programmers.


disadvantages for the Off-Shelf software :

1. The software doesn't meet the organization/business need exactly.

difference between written and off-shelf software :

Written / Custom Software :
It is specially made by the skillful and expert programmers that is specifically written for the purpose to carry out or to perform the required task that is fulfill the organization needs or individual..

Off-Shelf Software :

this is the ready-made software which can be easily found at every computer shop.

TOPIC 4 :

** application softwares **

the differences between written software and off-the-shelf software