I'd like to raise a flag. I've seen many answers containing a link to an often very well documented website. However, the idea of SE sites is to aggregate knowledge as a one-stop resource. Links can expire, and if this happens, any person browsing that answers in the future will find something completely useless as an answer.

How to fix this? We cannot copy from another site, clearly, but it can be reformulated. The biggest issue is with schematics. I doubt anybody would waste time copying a circuit schematics and uploading it to imgur.

I don't really have any strong solution, but I do see a problem for future readers, and I welcome your comments.

• You can just copy from another site, if the site is under a free license, like Wikipedia. Oct 27 '10 at 19:14

I just got a reply to a comment on meta.SO [over here][2] from Jeff Atwood♦ himself, linking to a blog post which reads:

Alan Schaaf, the man behind Imgur, generously provided us a network-wide “pro” account that keeps any images hosted through our websites around indefinitely.

So, you can ignore my previous, misguided answer. Imgur images are permanent through the SO uploader.

The new policy should be to link to any images on the web (including schematics) using the image button. Then, remove the ! at the start of the link to make a hyperlink to a permanently hosted image if the image is too large or distracting from the answer.

However, I think that a part of the question which was originally raised was with respect to links to textual pages. I don't know what the magic number of lines is, but 10-20 line excerpts should probably just be quoted (with attribution/a link, of course), while long quotes (a screen height or more) should be just linked with a summary and/or spotlight quote in the answer (like my reference to the blog above).

I doubt anybody would waste time copying a circuit schematics and uploading it to imgur.

Uh, that happens automatically when you inline an image from another site. Copying and pasting the google logo url like this:

produces this:

![alt text][3]
...
[3]: http://i.stack.imgur.com/dTYuL.png

• this assumes you are actually allowed to do it. hotlinking can introduce intellectual properties issues, and you are using someone else's bandwidth. Oct 4 '10 at 15:37
• It's not hotlinking. Oct 4 '10 at 19:51
• And most uses of images on this site would be qualified as Fair Use, I would think. Oct 4 '10 at 19:52
• @Stefano, like endolith says it's not hotlinking, it's far worse! :-) You're copying the content to your own site, so the bandwidth is not an issue. Fair Use seems reasonable to me. You can also tell where you got the image. Apr 9 '12 at 7:38

I would definitely take the time to upload schematics to an image host when they're on a site which might change. If it's coming from Wikipedia or the like, then I won't bother. However, imgur is not permanent, either. From the imgur FAQ:

How long do you keep the images? As long as images are getting at least 1 view every 3 months, they will stick around forever. After that, your image may be removed to create more space for newer images.

Flikr and ImageShack both say that they'll keep your images for as long as you have an account, but that's not what we need. We need it to exist as long as the question exists, which means StackOverflow Internet Services hosting. Currently, imgur is used as a third-party image host. Does anyone know if SO has a special contract with imgur to keep images longer?

We need a simple schematic editor/local schematic host in the same way that MathOverflow needs an equation formatter. We've had a discussion on this before, but nothing really came out of it.

Edit: I just realized what it means for StackOverflow to have a code formatting tool in the editor. This is an acknowledgment that a site about coding needs a standard, hosted tool to share code snippets. Imagine if formatted HTML or various image hosts, (resplendent with the various background colors, highlighting formats, and fonts used by different programmers) were the only way to share code on SO. I think that it's hard to argue that our site is any different - We just need to work with schematics.

• In the past I've uploaded stuff to imageShack, just to post it on here, is it not possible to have an image hosting button integrated into The Electronics and Robotics Exchange?
– Jim
Oct 4 '10 at 14:29
• if you click the link to add an image it will let you upload an image from your computer. This is then hosted on imgur automatically. it is i.imgur.com/H56rS.png No work on my part. Oct 4 '10 at 15:36
• I had previously uploaded stuff to imgur to link to from this site when I didn't want to fill up an answer with less relevant images. Should links ending in *.png or *.jpg etc. automatically be uploaded/linked to from imgur? Oct 4 '10 at 16:19
• if you need to upload an image, you can click the button as you upload the image and select web or computer image and it will auto upload it to imgur and link it. Oct 4 '10 at 21:00