Full, differential, incremental - three words that decide how much space your backups eat and how fast a restore goes. Here they are in plain language, with one weekly pattern that works for most PCs and the one file-management rule you must never break.
A backup definition in Reflect can run itself: one full image, then smaller backups that only capture what changed. Choosing between differential and incremental is the only real decision, and it is a simple trade between disk space and restore simplicity.
One week of the pattern from this guide. Bar lengths are illustrations - your incremental sizes follow how much your data actually changes each day.
Reflect's built-in templates exist for this, and the classic shape is: one full image a week (Sunday night, say) and an incremental every other day or daily. Retention keeps roughly three to four weeks of history and deletes the oldest sets automatically.
Reflect also offers an Incremental Forever style template, where after the first full, only incrementals run and old ones merge into a synthetic full in the background. It is the lowest-effort pattern of all - one full, then small dailies forever, with retention deciding how far back you can travel.
Take a PC whose full image measures 120 GB. Daily incrementals on a normal office PC are often just a few GB each - say 3-6 GB - because most files never change. A month of protection then costs roughly one full plus a modest pile of small files, not thirty full copies.
Differentials tell a different story by Friday: the file holding five days of changes can reach a third or more of the full's size. That is the honest trade - differentials buy simpler restores with disk space; incrementals buy space with chain discipline.
That pile of image files in the backup folder is a set, linked in order. Deleting one incremental from the middle by hand can make every later restore point in that chain unusable. Always let Reflect's retention rules remove old backups - it deletes whole expired sets, never links out of a live chain.
And if the schedule time finds the PC switched off, check the definition's option to run missed backups at the next start; a backup habit with silent gaps is how three-week-old images happen.
See every click in Macrium Reflect - the image, the settings and the restore - live in the full video.
▶️ Watch Full VideoIncremental, for most people - it uses far less space, and Reflect manages the chain for you. Choose differential only if you strongly prefer a two-file restore and have the disk space for its mid-week growth.
Restore points from that link onward in the chain can become unusable - the chain is only as strong as its files. Earlier restore points and the full itself remain fine. This is why verification and hands-off retention matter.
For most home and small-office PCs, three to four weeks is the sweet spot: long enough to notice a slow problem and still travel back before it, short enough to keep the backup drive affordable.