Many times we need just a part of picture and there comes the use to remove the rest complex part of that picture.
It can also be the case when we need to convert a .gif or .png file.
The whole thing can be done using the photoshop. The below steps indicates the same:
1.lets taking the example of a picture and opening it in photoshop.
2.from tools select the magic tool as shown in picture
NOTE: make it a layer first.
4.thats the final step just save ur final pic in .gif or .png file as you reqire.