What ⧧ means
It marks the end of a computer data record. Its Unicode name is “thermodynamic,” and its formal alias is “record mark”; that name does not define a universal operator in thermodynamics.
A data record is a stored unit of information. In 1950s computer formats, the mark showed where one ended, especially when records varied in length.
⧧ vs ‡: how do they differ?
They are distinct characters with similar shapes.
A Unicode review in 2017 discussed whether the record mark should be unified with the existing double dagger because readers can confuse the forms.
Some technical documents use ‡ as a visual stand-in for ⧧. That substitution does not make the characters interchangeable.
Specialist and historical; without a nearby definition, it reads as technical notation.
Do not treat ‡ as the record mark.
Don't confuse it with
1Questions people ask
1Why does ⧧ show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type ⧧
⧧\29E7Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.