"All I see is last-week's column!"

Readers have occasionally said that when they visit the site, they see the column for the previous week. What is the problem?

It is not a problem with the column. But before I explain, let me suggest trying any of the following to load the latest version:

1. Go to the Snapshots home page and click on your browser's REFRESH icon.
2. The new column may be available in the annual index - under "Past Columns" above.
3. Wait ... the problem will pass.
Refresh icon

While this may be frustrating, it actually is "normal." Let me explain.

While the column is typically posted by 10 a.m. on Friday, occasionally it is done much later in the day. If you are one of the people who is on the ALERT list, when you receive that message, it HAS been posted as the alert is always sent AFTER posting.

But there is a much more common reason for this problem. When a person requests a web page, the computer browser does NOT immediately send that request out on the Internet. Instead, it looks into what is called the browser cache. As a person uses his browser, copies of the pages visited are saved for a time in this storage area. (This is one of those areas the police look at when they want to know what someone has been looking at.)

If there is a copy in the cache, the browser will show it rather than retrieve a new one from the Internet. This makes the system faster and cuts down on traffic on the Internet, but if the page has changed since the copy was saved, the user sees an older version. Since most pages don�t change often, this is USUALLY fine.

Many things have an effect on how long these copies are saved and used. One of those is the size of a page. Big home pages - such as those for a newspaper - contain a large amount of data and so use a lot of space. So the browser may give them the boot after a short time. But the Snapshots home page is petite and so may persist for some time.

A browser may check how old its copy is and have a rule for how long it considers it "new." Imagine a person tries to see the column and it isn't posted yet. The browser requests the page, but will receive last-week's column. It then saves it. Until the time passes, the browser will consider the one in the cache as current and so future attempts to see the column will cause the browser to use the older one it is saving, even after the new one is posted. Husband Art has seen this happen when using his laptop and his smartphone at the same time. The laptop browser served the one from its cache, while the phone didn't have one in its cache and so requested a fresh copy. The result was the laptop had an older version and the phone had the new version.

When you click the REFRESH icon, the browser is supposed to make a request for a fresh page. But many browsers will return the cache page for some time. (If you are tech savvy, this can be avoided by clearing your browser cache as that dumps all copies.) Different browsers play by different rules. This problem seems to be much greater with Chrome.

But there are other ways the problem may occur. The Internet has its own caches. In that case, all you can do is wait until they are updated.

So why hasn't anyone experienced this problem before? Everyone has, they just were not aware of it. Few sites send out an e-mail announcing a change has been made. So even with newspaper sites, when someone receives an older version from their browser's cache, they assume the site has not been updated yet, even though it may have been.