Terminology

Save
A save is a term derived from "saving throw", a term originating from tabletop role playing games as a defensive check to see if a player will take or avoid a harmful effect. Saves are usually referred to in the context "a (attribute) save of difficulty (number)".

By default, this is a roll that has the attribute's modifier added to the result. If this is greater than the difficulty specified, the "save" is successful and the attempted effect to apply will be ignored.

Tier
In general, a tier represents the minimum level or a strength indicator of something. The tiers range from 1 to 8. Each tier is about 5 levels. Tier 1 is levels 1-4, tier 2 is 5-9, etc. This is for creatures, items, and terrain.

The following articles provide more detail about tier within specific contexts:
 * Zone tier - the tier of particular zones (or "screens")
 * XP tier - the tier of the player and other creatures for purposes of calculating experience gain.

Tier as such is fundamentally game-mechanical, primarily representing a design evaluation of roughly where something should be encountered in terms of player progression and/or exposure to danger.

A related concept that is sometimes tied together with tier and sometimes not is tech tier, which represents the degree of technological sophistication required to create an item from scratch. The general idea of the tech tiers looks like:

= Units of Measurement = The names of units used in the game, while drawn from outside sources, do not obviously correspond to how they are used in real life. In many cases, there is no consistent interpretation of what a unit translates to in conventional terms (for example, all lengths of wire weigh the same).

Dram
A dram (plural drams), written in game as a yellow or a cyan  is one unit of liquid volume. The liquid capacity of all containers is measured in drams. At the same time, drams is also used as the unit of currency, where one dram of fresh water is the base unit of all transactions.

Relation to other units
For most liquids, 1 dram of liquid weighs 0.25 pounds. The weight system truncates any decimal points, so 7 drams of such a liquid will weigh 1 pound in your inventory. Liquids of differing density are:

Pound
The Pound (plural Lbs.) or is the sole measure of weight. The symbol is a pun on the imperial mass measurement, where # is also known as the pound symbol. Despite this, there is no evidence that a pound/hash is equivalent to a real life pound. On this wiki, we previously avoided referring to this weight unit by using Template:Pounds or # wherever possible; in newer versions of the game, Lbs. is now visible in game and is the official name.

T
T is a unit used to measure temperature. Fresh water will freeze at -100T, and will evaporate into steam at 650T. The default ambient temperature of a character and the world is 25 T. It is also represented as °.

Parasang
A parasang is one tile on the world map. These are comprised of 3x3 zones of 80x25 cells, for a total of 18,000(240x75) cells. Because a parasang is not a perfect square, the length of a parasang differs depending on the axis that it is measured. This disparity is not calculated in game, however. Moving in any direction will cost the same movement cost.

Stratum
A stratum is a single level of vertical distance, generally down. The plural form of stratum is strata. The precise scale of a stratum is unclear, as a combination of the abstractions of gameplay and the advanced sciences of the Eaters allow enormous objects to exist in otherwise small spaces.

Zone/Screen
A zone or screen is the visible play space, which is a 80x24 grid of cells.

Cell/Tile/Square/Space
Cells, tiles, squares, or spaces are the base unit of physical distance. Every object will take up one cell.