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This is how you change stroke width and alignment in Adobe Illustrator. So what we're going to do is we're going to go to our tools panel and we're going to actually, this time, we're going to use the pen tool. We're going to click this and what we're going to do is we're going to click one point anywhere on your art board. It doesn't matter where you click. It can be anywhere - top, bottom - it doesn't matter. And then we're going to click a second point. And what you'll notice is that upon doing that, we have one nice, long line segment.
And since this is just a line segment, we're going to remove the fill from that. So we're going to go down to our panel and if this is already the top square as opposed to this back square, we'll remove the fill by clicking this little icon, which says "None", and it will remove the fill, just to be safe. Now we can look at this line segment and see that it's a stroke. It's just one point to another. That's essentially what strokes are. At one endpoint, at another endpoint, they can be open-shape or they can be close-shape, one or the other, but either way, they're essentially a line segment. And we can change the weight of this line segment and how thick it is, hence the width, by going to our stroke panel.
Now if this panel isn't present, we would click in our Windows menu and we would scroll all the way down to stroke and then it would come up on our right window panel. Over here on the right, you'll notice that it has an option that says "Weight." Now if we want to change this, we can lower it and you'll notice that our stroke is actually getting thinner. Or we can increase it and you'll notice that it gets thicker. That's one way that you can actually change the width of a stroke.
Now another way that they just recently introduced in probably the CS5 and up is the Stroke Width tool. And if you go to your Tools Panel, you'll notice there's this funny-looking tool. It's called the Width Tool. And if you hover over it, you'll see the shortcut key, the hot key to actually get to it. We're going to click that. What we can do is when we use this tool and we hover over this, you'll notice that there's a little white circle that's following your cursor. And your cursor times tool and out with a plus sign. And you can click there and you can actually drag up and change the width. You can click that point and drag down and change the width, and you can also do that to multiple segments on the actual line itself. So that's an additional way that you can actually change the width.
And then if you have multiple line segments, you can actually align these by the entire shape itself or you can align them by the point that's on the endpoint. So we can select our selection tool. And we're going to select this endpoint. And let's say we want it to align to the endpoint of our other stroke, which is at the top. We would click that, go to our line panel, and we'd click Align to Selection, and then we would just align to wherever that selection is. So we would click right, left or middle. So we want to align the left side of this to the right side of this segment. And when we click that, you'll notice now the point is almost nonexistent. But if you would click on it again, you could always drag that out because the selection is still there.
And that is how you work with the width on line segments and aligning them.