Adobe Illustrator - What is the difference between a Layer and a Group?
I've made my first steps in Adobe Illustrator, and I like it very much.. I'm an expert in Photoshop so many things seemed familiar to me. There's one thing, I haven't been able to find an answer for on the net..
Maybe anybody knows this?
Layers and sublayers appear with a grey background in the layer window. Groups appear with a white background in the layer window. But they both seem to have an identical behaviour.
Is there any difference between a 'layer/sublayer' and a 'group'? Why does Illustrator distinguish them?
I'm using Illustrator CS2.
Thanks for your help! I really appreciate it.
Greetings
Christopher
Answer
Technically, there is very little difference. Internally, in the Illustrator artwork tree, both layers and groups perform the same function - they create a parent object that can contain one or more child objects. The differences lie in how they are used in a practical sense.
Groups are typically used to bundle artwork that you want to stay together when moving or scaling. For example, let's say you draw a door. It might contain inset panels and a door knob. When you want to move it, you can direct select each object or marquee select all the objects before moving, but that is slow and can also pick up additional art objects that may be in the way. Alternatively, if you group the door outline, the inset panels and the door knob, now all you need to do is click once on any of those objects to select the entire door.
Layers are typically used to manage visibility and stacking order. For example, let's say you draw a floor plan for a home. On one layer you might draw the walls. Then, on other layers you might draw electrical plans, furniture layouts, and plumbing plans. When you contract with an electrician, he may not need to see the furniture layout, so you would set the visibility of the furniture layer to false so that the printout would not contain any furniture. Also, you need to ensure that furniture is always drawn over walls, so you would use the layer panel to move all furniture at once above the walls layer.