APR
Annual percentage rate: a yearly way to describe the cost of borrowing, often including interest and certain fees.
Example: A loan with a 7% APR may cost more than 7% of the original amount once the full payment schedule and fees are considered.
Plain-language reference
A glossary for the words behind the numbers.
These are terms you may see in the calculators and guides on this site. Each definition explains what the word means and where it matters.
Glossary category
Money
Terms that appear in budgeting, borrowing, saving, shopping, and everyday price comparisons.
Compound interest
Interest calculated on the original amount plus interest that has already been added.
Example: When savings earn interest, the next period can earn interest on both the deposit and the earlier growth.
See it in contextContingency
Extra money set aside for costs that are possible but not known exactly yet.
Example: A moving budget might include a 10% contingency for delays, parking, or extra supplies.
See it in contextPrincipal
The original amount borrowed or the part of a loan balance that is not interest.
Example: When a payment reduces principal, you owe less before the next interest calculation.
See it in contextUnit price
The cost of one equal unit, such as one ounce, pound, liter, or item.
Example: A larger package is not always the better value; compare its price per ounce with the smaller package.
See it in contextGlossary category
Home and projects
Terms used when estimating supplies, space, energy, moving costs, and household projects.
Coverage
How much surface a product is expected to cover, usually for one container or one coat.
Example: Paint coverage may be listed as square feet per gallon. Texture and surface condition can change the real result.
See it in contextCubic feet
A unit of volume describing three-dimensional space: length × width × height when each measurement is in feet.
Example: Concrete, gravel, storage space, and some packing materials may be estimated in cubic feet.
See it in contextKilowatt-hour
A unit of energy equal to using 1,000 watts for one hour.
Example: An appliance using 1,000 watts for two hours uses about 2 kilowatt-hours.
See it in contextYield
How much finished material a product is expected to make or fill.
Example: A bag of concrete mix may have a stated yield in cubic feet; different products can have different yields.
See it in contextContingency reserve
A budget cushion added to a planned subtotal; it is not a guaranteed charge.
Example: A reserve can help cover a moving delay, extra labor, or a last-minute purchase.
Glossary category
Measurement
Terms that help explain numbers, units, dimensions, and the space or quantity they describe.
Area
The amount of surface inside a boundary, measured in square units.
Example: A 10-foot by 12-foot room has 120 square feet of floor area.
Conversion factor
A number used to change a measurement into another unit of the same type.
Example: There are 2.54 centimeters in one inch, so inches can be multiplied by 2.54 to get centimeters.
See it in contextMass
How much matter is in something. Everyday labels often use the word weight for mass.
Example: Grams, kilograms, ounces, and pounds are commonly used to label mass.
Pitch
The distance from one metric thread crest to the next, measured in millimeters.
Example: An M6 × 1.0 fastener has a 1.0-millimeter thread pitch.
See it in contextTPI
Threads per inch: the number of thread ridges counted along one inch of a threaded fastener.
Example: A 1/4-20 fastener has a 1/4-inch diameter and 20 threads per inch.
See it in contextVolume
The amount of three-dimensional space something occupies, measured in cubic or liquid units.
Example: A rectangular box’s volume is length × width × height.
See it in contextGlossary category
Electronics
Basic electrical terms used by the low-voltage learning tools.
Ampere (amp)
A unit of electric current: the rate at which electric charge flows.
Example: A device drawing 2 amps uses twice the current of a similar device drawing 1 amp under the same conditions.
Ohm
A unit of electrical resistance, which describes how strongly a component opposes current.
Example: A higher resistance usually means less current for the same voltage.
See it in contextResistance
Opposition to the flow of electric current, measured in ohms.
Example: Ohm’s Law relates voltage, current, and resistance: V = I × R.
See it in contextVoltage
The electrical potential difference that can push current through a circuit.
Example: A 12-volt source can produce different currents depending on the resistance of the load.
See it in contextWatt
A unit of power: the rate at which electrical energy is being used or transferred.
Example: A 60-watt bulb uses power faster than a 10-watt bulb while both are running.
Glossary category
Dates and health
Terms used for calendar calculations and educational nutrition estimates.
Calendar age
Age counted using completed years, months, and days on the calendar.
Example: Calendar age is not always the same thing as dividing total days by 365 because months have different lengths.
See it in contextMacro
Short for macronutrient: protein, carbohydrate, or fat, which provide energy and building material for the body.
Example: A macro plan may describe a daily calorie target as percentages and grams of protein, carbs, and fat.
See it in contextMPG
Miles per gallon: how many miles a vehicle can travel using one gallon of fuel.
Example: At 30 MPG, a 300-mile trip takes about 10 gallons before real-world conditions are considered.
See it in contextPace
The amount of time needed to travel one unit of distance, such as minutes per mile.
Example: A faster pace has fewer minutes per mile.
See it in contextTDEE
Total daily energy expenditure: an estimate of how many calories a person uses in a day.
Example: TDEE estimates depend on body details and activity, so they are starting points rather than medical prescriptions.
See it in contextA glossary is a starting point
A definition can explain a word without deciding whether a product fits, a structure is safe, a loan is affordable, or a medical choice is appropriate. Check the current specification, official guidance, or a qualified professional when the decision has important consequences.
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