You need mask for complicated selections. If you have a bunch of objects in composition, you could use mask for faster and more productive work.
Mask will be saved as Alpha channel in CHANNELS panel (Window > Channels).
Dialog in which you can improve selection actually layer mask and remove all selection or layer mask imperfections using several commands like feather,smooth, contrarst..
With selection tools available in Photoshop like: Lassso tools, Magic Wand, Quick selection. With selected pixels you can do whatever you want: delete them, change or mask or create new layer from selected pixels.
Photoshop have Horizontal Type Tool and Horizontal Type Mask Tool which you can use to type text in Photoshop.
Softening, you can soften edges of selection using Feather command from select > Modify > Feather or From Refine Edge dialog Select > Refine Edge. Feather also appears on Properties panel in Photoshop CS6 or Masks panel in previous versions to soften edges of pixel based or vector mask (you must select mask on Layers panel first).
Just like the mask in the real life.The mask option also works the same way.The mask option in the Adobe Photoshop allows you hide the part of the picture or graphics created using Photoshop.You club the mask option with other options available to create new effects.Mask option works the same way in each and every other soft-ware of Adobe.
Vector mask is mask which will be added to layer automaticaly when you work with shapes in Photoshop. There are two types of masks-layer masks and vector masks. Both control which parts of an image or layer will be hidden or revealed, and the masks can have special effects and styles applied to them. (See related link)
Use unsharp mask to sharpen picture and bring more details to an image.
Yes you can, for example people usually use Filter > Blur > Gaussian Blur filter to soften edges of the mask.
With Quick Mask there is no some extra benefits. Benefit is that You can paint over image with black or white and see Your mask immediately at full size view on screen. Benefit is also that You are controlling which parts will be hidden and which visible in other words mask do not depend on automatic features in Photoshop which in most cases makes selections based on levels.
There are many ways to select the part of the picture you want to cut out. Once you do select the area you can hit copy from the edit menu and paste onto another photo you want to in Photoshop.
Not at all really just the picture where link is and the mask is different not the actually picture.