White Square □ vs Black Square ■ vs Rectangle ▭: How Are They Different?
□, ■, and ▭ share a box-like silhouette, but fill, proportion, and the underlying character separate a square from a rectangle.
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Practical guides for identifying symbols, understanding Unicode, comparing look-alike characters, and working with special characters across devices.
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Unicode, symbols & special charactersWhite Circle ○ vs Black Circle ● vs Bullseye ◎: What’s the Difference?
○ is an outlined circle, ● is filled, and ◎ is a bullseye. Those visual differences are encoded as separate characters, not as states of one symbol.
Read guide →Diamond ◇ vs Lozenge ◊ vs Black Diamond ◆: What’s the Difference?
◇ and ◊ can look almost identical in some fonts, while ◆ adds fill to the same general family of shapes. Their Unicode identities are still different.
Read guide →Triangle ▶ vs Right Arrow →: Why They Are Different Symbols
▶ and → can both point to the right, but a triangle, an arrow, and a media-control icon are different things even when an interface gives them…
Read guide →White Square □ vs Ballot Box ☐: What’s the Difference?
□ and ☐ can be nearly indistinguishable in a font, yet one is a general geometric square and the other is an explicit ballot-box character.
Read guide →Circle ○ vs Letter O vs Number 0: How to Tell Them Apart
○, O, and 0 can collapse into the same-looking round mark in a small font. Their jobs in the text—and the underlying character—tell them apart.
Read guide →m vs M in SI Units: Metre, Milli, and Mega Explained
Lowercase m can mean metre or milli depending on position; uppercase M means mega. Case and spacing are part of the SI expression.
Read guide →k vs K in Measurement: Kilo Prefix vs Kelvin Unit
Lowercase k is the kilo prefix; uppercase K is the kelvin unit symbol. In SI notation, case is part of the meaning, not a styling choice.
Read guide →Litre L vs l vs ℓ vs 1: Which Symbol Is Correct?
Both L and l are accepted litre symbols. Script ℓ is a related historical character, and uppercase L is often preferred because it is harder to confuse…
Read guide →Arcsecond ″ vs Second s: How to Tell Angle from Time
Arcseconds use the double prime ″; seconds of time use s. The same ″ character can also mean inches, so context matters.
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