Hello,
Today I am going to show you everything about Adobe Illustrator’s Pen Tool. I hope you will find this tutorial useful, and i hope that it will be easy to understand.

Pen Tool is one of the most difficult tools in Adobe Illustrator - after Mesh Tool probably – and this is why most people avoid it. Actually you can find this tool in other programs too, such as Adobe Photoshop, Adobe Fireworks, Corel Draw, etc. and is based on Bézier curve principle (a parametric curve). It is used to draw smooth , easy to modify, vectorial curves. There are several numbers of tools which help you modify this curves, but we will get to this later on in the tutorial. First, you can see in the image below what is the icon for Pen Tool and where it is placed on tools panel.
Now that we know where to find our tool, we can start discovering what it can do. First, let’s set the fill none and stroke black for our upcoming paths.

With Pen Tool you can make curves or straight lines. To actually do the lines, you just click on the artboard – to make the straight lines, or click and drag – to make the curved ones. Either way, each time you click/click – drag you create a point on your artboard called “anchor point”. The Anchor point looks just like a little square – it is filled with color when it is made last, or when it is selected; otherwise it is like a white square with stroke. Here is a single anchor point: 
You can make straight lines, just by clicking around like in the image below:
To make curved lines you click and then drag in the direction that you want your line to curve, like drawing a tangent for the curve you want to draw. If you want to make a hill just drag to the top; to make a valley drag downwards.
The secret of making smooth curves is to put as few anchor points as you can and always place them at the sides of the curves, not at their tops/bottoms. See two examples of correct and incorrect placing of anchor points below:
If you want to know how far to drag you must think at this: the farther you drag, the steeper the curve will be. This is all because the beginning of the curve will always stick to the handle, and the longer the handle is more (on a longer distance) will the curve stick to it:

If you left a path open, just go with the Pen Tool over an anchor point (at one end of the path) and when you see the slash under the cursor icon just click/click-drag an than you can just continue your curve as you wish.
We have seen how to create the paths, but what if you make some mistakes, or you just thik of modifiing the curves you just made? I will tell you how to do this and what are the tools used for this kind of job.
1. To modify the curbing of a line segment, selecting anchor points, moving anchor points, deleting points or paths or repositioning the handles we use Direct Selection Tool (A);
2. To convert a smooth point into a corner point or vice versa we use Convert Anchor Point Tool (Shift+C);
3. To add anchor points we use Add Anchor Point Tool (+);
4. To delete anchor points we use Delete Anchor Point Tool (-);
Note: we find tools 2, 3, and 4 in the drop down menu of Pen Tool in Tools’ Panel.
5. To split a path into several paths just use Scissors Tool (C);
Note: tool number 5 is found in Eraser Tool‘s drop down menu.
6. To erase parts of a line segment we use Path Eraser Tool – placed in Pencil Tool drop down menu.

Select an anchor point by clicking once on it. To select more drag and drop to make a selection rectangle that includes the anchor points you want to select. Or you can just ckick on every anchor point you want to select while holding down Shift Key on your keyboard.

If you want to modify curved lines you just have to use Direct Selection Tool (A) and drag the curve with it. This however will work this way (changing the way a line curves) only for curved lines. For straight lines the same techinique will simply move the line.


With Direct Selection Tool (A) you can move an anchor point or more. To move the selected anchor point/points, just go to one of the lines between the selected anchor points and just drag and drop them wherever you want.

To delete anchor points or line segments, just select the anchor points you want to delete (or the anchor points at the end of the line segment that you want to delete) and then hit Delete Key on your keyboard.

To convert a smooth point into a corner point just click on the anchor point that you want to modify with Convert Anchor Point Tool (Shift+C). To make a smooth point from a corner point click and drag on the anchor point that you want to modify. Then just play with the handles because they can be moved individually with this tool.


To add anchor points just click with Add Anchor Points Tool (+) on your path, where you want to place the new points.

To delete anchor points just click with Delete Anchor Points Tool (-) on the anchor points that you want to delete.

We use the Path Eraser Tool to erase only a part of a segment, by passing the tool several times above the part of the line that we want to erase. It is like using an eraser on a pencil line. This also make from one line two separate segments, and the path also separates.


Scissor Tool (C) splits a path into two paths. Just click on the path where you want to split it and click there. Afterwards you will have two different paths. But, unlike the Path Eraser Tool it will not erase any part of the path.
Tips:
Hold Shift Key while making a new anchor point by clicking, and the new anchor point will be aligned with the previous one.
Hold Shift Key while making a new anchor point by click-drag and the handling will be oriented at 0, 45, 90, 135, 180, 225, 270, 315 degrees
To make a corner point when making a curve (not waiting until after the curve is done to modify it with Convert Anchor Point Tool), just click on the last point that you have done with Pen Tool once, and then just make another point to see the result.
That’s it folks, thanks for reading and I hope it helped you.
For any questions, just leave a comment!!
Hariana