Your phone battery icon often displays % — the percent sign. It shows how much of the total charge remains. The % symbol evolved from the Italian phrase "per cento" (per hundred), where the o gradually turned into a slash.

Wi-Fi icons use ∫-like arcs to represent signal strength. The "greater than" symbol > appears in file menus, text direction indicators, and nested comment threads. The Bluetooth logo combines the Younger Futhark runes for H (ᚼ) and B (ᛒ).

The * (asterisk) hides passwords on screens. On keyboards, ±, °, ≠, and ≈ appear in the emoji/symbols panel. The @ symbol — originally an accounting abbreviation for "at the rate of" — is now universal in email and social media.

The # (number sign / hash / pound) started as an abbreviation for the Latin libra pondo (pound weight). On social media, it creates hashtags. In music, ♯ (sharp) and ♭ (flat) are close relatives — the hash is actually two horizontal lines, while the sharp has two vertical lines.

Store windows display % for discounts ("50% off"), − for markdowns, and ÷ when splitting bills. Price tags compare "was" vs "now" — a real-life use of greater-than and less-than thinking.

Grocery receipts use = (total), × (quantity × price), and + (subtotals). The total at the bottom — that fundamental = — is Robert Recorde's 1557 invention at work every time you shop.

Currency rates use ≈ (approximately equal) because exchange rates fluctuate. Symbols like $, €, £, and ¥ are themselves mathematical shorthand — the dollar sign evolved from the Spanish peso abbreviation "ps."

The ° (degree) symbol appears on every weather app. °C (Celsius) and °F (Fahrenheit) are among the most widely seen math symbols. The − (minus) sign indicates below-freezing temperatures.

GPS coordinates use ° for degrees, ′ for minutes, and ″ for seconds. Maps use ∠ for turns, ⊥ for perpendicular streets. The ≡ symbol on road signs means "highway" (a triple line suggesting a multi-lane road).

Road signs show steep gradients as % (e.g., "10% grade"). Hiking maps use △ for mountain peaks and ≈ for approximate trail distances. Weather maps use ∞-like isobars for pressure systems.

Every sports scoreboard uses : (ratio) for scores like 3:1. Batting averages in baseball, free-throw percentages in basketball, and save percentages in soccer all use . (decimal) and %. League tables use > and < implicitly when ranking teams.

Dice use the ∑ concept — the sum of two dice forming a probability distribution. Games use = for matching, ≠ for differences. The × symbol marks a space on many game boards. Card suits (♠, ♥, ♦, ♣) are symbols with medieval origins.

Tournament brackets use > to show elimination paths. The winner is the maximum (max) of all match outcomes. ELO ratings in chess use ≈ to estimate expected scores. Olympic scoring often removes the highest and lowest — a statistical x̄ (mean) operation.

Tape measures use ″ (inches) and ′ (feet). Recipes use / (fraction) for measurements like ½ cup. Oven temperatures use °. The ≈ symbol applies when estimating ingredient quantities — "about a teaspoon."

Carpenters use ∠ for miter cuts, ⊥ for right angles, ∥ for parallel cuts. The ° symbol measures angles for crown molding and stair stringers. A standard 90° corner is everywhere in construction.

Power symbols combine ○ (off) and | (on) — a binary 1/0 notation. The ∞ symbol appears on dimmer switches and fans for "variable" settings. Washing machine dials use ≈ for approximate cycle times.

Restroom signs use △ and ▽ (up/down triangles) for stairs and escalators. The ! (exclamation) marks warnings. The ✓ (check mark) indicates completion, approval, or selection.

Your car uses ° for temperature, % for fuel efficiency, × and ÷ implicitly through the trip computer's calculations. The ∼ symbol means "approximately" on the fuel gauge.

Blood pressure readings use / (e.g., 120/80). Drug dosages use × ("take 1 tablet × 3 times daily"). The μ (mu) prefix means micro — as in μg (micrograms) and μm (micrometers). The ± symbol shows margins of error in medical studies.