Usually an Amazon.com product page has an excruciatingly long address (or “URL” as it’s technically called). For example, this links to The Da Vinci Code:
Not too long ago, Amazon.com created a way to shorten their links significantly, making it much easier to include them in e-mails (where a very long link can be “word wrapped” and fail to work) or blog posts. Amazon.com refers to these as “Permalinks.” The shorter links look like this:
The first part is Amazon.com’s domain name with a few vowels missing, and the second part is the ISBN number of the item in question (if the item is not a book, the ASIN or “Amazon Standard Identification Number” will be substituted).
While you can create these links yourself by substituting the appropriate ISBN or ASIN number, the easier way is to navigate to the product page you wish to link to, then click the “Share with Friends” link located right side of the page (just below the “Add to Shopping Cart” button). A window will pop up with the Pemalink, which you can copy and paste where you need it.