These two terms are of times confused. A backup is a copy of your data held somewhere to address the loss of a data storage device. An archive is a non-current data set; it too needs to be backed up to insure against loss.
There comes a time when a large number of the files we keep on a hard drive are inactive, but still important to us. In the past, memorabilia such as photos, news clippings and similar items were easily kept for future generations simply be scrapbooking or placing in a storage container, sometimes as simple as a shoe box. The more fastidious among us may annotate these items with names, dates and locations, but in many cases, even the simple step of making notes on an envelope of photos is lacking.
As this volume of information increases, and the devices we use most frequently have smaller storage volumes, the need to maintain an archive increases. We need to create that digital shoebox to contain all the important, but non-current information. The challenge is that many forms of digital storage degrade over a time span often measured in years, not decades.Mechanical devices break down, magnetic data degausses, even CD or DVD data loses its integrity with time.
The effort needed to maintain important digital files is much greater, and needs to be a continuing effort - there is no option to set it and fuggetaboutit! Any digital document or photo will need to be updated to new media on a regular basis, and may need to be converted to a new file format on occasion. Our propensity to take more photos and save more items makes this an ever greater challenge as the sheer volume of information retained has increased immensely. Event memories which might have been kept in a small snapshot in the 1940's, may now be hours of video or dozens of photos.
Here are a few suggestions to help plan for long term file retention: store your files in the most common format for longevity. Portable Document Format (PDF) for routine documents, and JPEG for photos are likely to have greater longevity than files stored in a proprietary format which may disappear in a software upgrade. Options for long term file storage include use of one of the big online suppliers of storage space such as Amazon, Google, or Microsoft. These files may have to be re-written on occasion to maintain integrity. Other options include backup services such as Crashplan, Mozy, or Backblaze. Home based storage might mean a pair of RAID drives, one of which is maintained off site. This options will again require upgrading of hardware at regular intervals, and re-writing of data. Other options to consider include the Transporter, a device which allows you to host a shared internet accessible network drive between individuals. The Transporter has been described as a "Personal Dropbox". One advantage is that you can create the initial clone at home quickly and without consuming internet bandwidth, then move it to a friend's place, and allow future updates to occur across the 'net.
Future article: What to toss; what to keep.