FATE is a FUDGE-based system. Standard FATE uses FUDGE dice (dF) as the randomizer, but can also use an alternate device of randomization such as a tarot deck (d14).

An example of the way things usually work:

1. GM determines the difficulty of something ("It takes a Great (+3) roll on Computers to hack that system.")

2. The player looks at their applicable skill ("I'm Good (+2) on Computers"), and rolls 4dF.

3. The skill level is modified by the roll and the results on The Ladder are compared. If the modified result meets the difficulty level of the task, it succeeds. ("I rolled a +1 net, raising my Good (+2) to a Great (+3). I succeeded.").

The Margin Of Success (MoS) is the degree to which you succeeded. In the example above, the MoS was 0 (a +3 was needed, and that's what was achieved), which is a marginal success (you just barely hacked to a command prompt). Larger MoS make for bigger, more significant, more impressive, longer-lasting successes (think "crit").

The Margin Of Failure (MoF) is the degree to which you failed. If in the above example the player had only rolled a Good, she would have had an MoF of 1 (no prompt, but probably no security alarms going off). A larger MoF is more significant in its disasterousness (think "fumble").

Note that the steps between different parts of The Ladder are few, and, thus, significant. That means a +1 bonus (for example) is profound, and a +2 is major. That has the effect of reducing the quantity of bonuses and disads for various things, mostly because they get lost within the step changes -- which, from a dramatic standpoint, makes perfect sense. Bond doesn't care if he gets hit by a S&W or a Glock, and certainly doesn't care much about the ammo being used...

Depending on the way the difficulty/goal(s) is set, and how many people are competing, you can have more complicated conflict/challenge resolution than this, as described in Tests And Challenges.