Think of the cloud: not the kind in sky, but the online storage system. The (likely) most well known is Apple's iCloud. iCloud allows you to access features like your calendar, pictures, music, notes, contacts, and more across a variety of devices...all with just an email and password.
iCloud, and other online data storage services, are almost like an enhancement of the brain: an enhanced, electric, memory. This memory is not stored in the the device in the palm of you hand or backed up to your computer at home. It is stored as non-tangible data across networks. The lack of tangibility of this data storage is directly related to the naming of the cloud- the non tangible object that is used to store non tangible information.
Now, instead of having boxes and boxed of faded photos where someones eyes are always shut because you don't get to check and re take photos, you have thousands of your favorite memories online that you can access from virtually any computer or smartphone. The idea of an undocumented memory is nearly obsolete.
To prove this point (of the lack of undocumented memories), while spending time with some friends recently, I tried to pay particular attention to how many times one of us reached for our phones to show something to the group. Though I quickly lost count, there was almost always someone on their phone looking for that part of the conversation, or a picture of their crazy dinner, or their new outfit or a picture of the latest man in their lives. Now I can tell you for a fact that none of this group would tell you that they don't use their phone that much, but we cannot even tell a simple story without looking at our phones to remind us of part of a conversation of show a picture. We do not even rely on our own memory; we rely on the memories stored on our phones (ultimately backed up to the cloud). We read aloud conversations we have and look at (and share) our pictures to tell a story about something yesterday. One seems to no longer say "I got in a car accident yesterday", but instead "look what happened to my car yesterday".
Not only are we able to recall our entire photo collection to the palm of out hands in mere seconds, but now we are also past the days of waiting in line for the new release of a CD.
We used to have whole set ups of CD-towers and binders in our houses and cars just to be able to have just SOME of your music with you to listen to in a semi private way. We are now able to store thousands of our favorite songs right on our cell phone! And if you do not happen to have the song you want- no more running to the store to buy an entire album, apps such as Spotify allow you to access any song you can think of instantly... on any device because all the data is stored in the enhanced memory of the cloud.