A backup of your computer is the best protection against hardware failure or against attacks by hackers with viruses or ransomware. A backup sometimes provides a solution also when you delete a file inadvertently. And yet, many people still forget to make a regular backup of their computer files. And what about your files in the Cloud? How do you secure them or is that not necessary?
Read all about how to proceed below.
Why is a backup necessary?
Your computer does not last forever. The constant writing and reading of files from and to your hard disc causes wear on that disc, which may lead to a disc failure: the hardware gives up the ghost. System files can become corrupt, however, for instance when your computer fails because of a power outage without being properly switched off. And then there are the computer viruses and all sorts of malware that threaten your files. Think, for instance, of the tidal wave in ransomware that has flooded the world in recent years: entire companies, hospitals, shipping companies were down for days because their files were locked by a hacker. Only after paying ransom did the companies receive the key so that they could use their files again.
If you have no safe copy of your files when such a disaster strikes, then you have a real problem. You can save documents on which you work in the cloud, via Dropbox, Microsoft OneDrive or Google Drive. But there are other important files that you will lose forever, if you have not made a backup.
Where should you keep the backup?
You can store the backup copy you make on different media.
- An external hard disc is an inexpensive solution. Make sure you have sufficient storage space and that this backup disc is not kept in the same place as your main computer, so as not to lose both of them, in case of fire, for instance.
- A USB stick is a good and rapid alternative. The disadvantage is that such a stick is usually limited in terms of storage space and can get lost easily because it is so small.
- CD or DVD: You can also burn a copy on a CD or DVD, but these discs are quite slower than hard discs or the flash memory on the USB stick. After some time, writable DVDs sometimes suffer from bit rot, which makes them less suitable for long-term storage.
- Cloud backup: Various commercial services offer you a cloud backup, against payment. The great advantage is that your data are in the cloud, and thus not at the same place as your computer. The disadvantage is that you have to take data use into account – a backup of 100 GB in files means also 100 GB in traffic. So the first thing to do is check whether your provider uses a maximum up/download load limit per month. One disadvantage is that if you apply no encryption, your data can be read by your cloud provider.
Which files should you backup?
The place where your files are located on your computer depends on your operating system (Windows, Mac, ...). But in general, you must certainly place the following files / folders in your backup:
- Your personal files: documents, music, photos, etc. Do not forget your OneDrive, Dropbox, and Google Drive folders.
- Your bookmarks or favourites in your browser. There are special applications for storing your logins and passwords securely.
- Your emails, contacts from your e-mail programme. Use your IMAP mail protocol, then all your e-mails will be secure on the email server at your provider. If your computer crashes, you can simply download them again. Your contacts are not however stored automatically on the server. If you work with the POP3 email protocol, then the emails that you have downloaded on your PC in the event of a crash are irretrievably lost if you have made no backup!
What is an incremental or differential backup?
With a full backup, you make an image, a reflection of your system, as it were. This takes the longest. All the files will not have changed however when you make a subsequent backup, and it would be mad to backup such files all over again. Therefore, after a first full backup, you can opt for:
- An incremental backup: only the files that have been changed will be backed up. The data are compared with your first full backup the first time, and then subsequent incremental backups are then compared with previous backups. The advantage is that incremental backups are made rapidly. But when you restore the files, you must first restore the full backup, and then the subsequent incremental backups, and that can take some time.
- A differential backup: here once again, only data that have changed are backed up, but the full backup is always used as reference. When restoring files, you need only the full backup and the last differential backup, which goes faster than for an incremental backup. The disadvantage is that the longer since the full backup was made, the more data have changed, and the longer it will take to make a differential backup.
What’s the difference between a copy and a backup?
Isn’t it simpler to just make a copy than a backup, you might ask? Both methods have advantages and disadvantages.
+ Copying folders and files goes much faster.
- Some files will not be copied because they are still in use, such as the Windows register, for instance.
+ A backup is made of all files, including hidden and protected files.
+ You can have a backup task carried out automatically at regular time intervals.
+ You have three options for a backup: full, incremental and differential. If you opt for the latter two, then only files that have changed since the previous backup are transferred anew to the backup medium. You forego a great deal of data traffic in such cases, particularly for backups in the cloud!
- A backup can take a long time, particularly the first time. But you can carry out the backup in the background, at the time that your computer is not used.
What does making a backup entail in concrete terms?
This depends on your operating system. Both Windows and Mac have a system for reversing changes on the operating system itself. With the Mac, you can retrieve files also with the Time Machine.
This is how to make a backup for your Mac.
So, put it down in your agenda at once: 31 March: make a backup!