Write mathematics, in any direction.

Derivatives, integrals, limits and series worked out inside the document, each step naming the rule it used — the product rule, L’Hôpital, integration by parts — in English or in Hebrew.

In a paper f is a function and a is a number, and the notation never says so. Write f(x) = x^2 once and the calculation knows what f′(x) and f(3) mean — it works on your paper, not on symbols in general.

Say “a unit circle with an inscribed square” and get a real TikZ figure — compiled before it is offered to you, so what you see is what will print. The picture is stored in the document, so it still shows on a machine with no TeX.

Send a link and you are both writing in the same document at the same time. You see each other’s caret, in its own colour with a name beside it. Nobody waits for a turn, and nothing is overwritten.

Manifold suggests how the sentence you are writing might finish — in English or in Hebrew. The model runs on your own machine, so what you write never leaves it.

Spelling and grammar in English and in Hebrew, on your own machine. The Hebrew check reads things a dictionary cannot — a counted number wearing the wrong gender, say.

Python, C, Rust, Haskell, SQL, pseudocode and more, set as programs rather than as paragraphs. The completion offers the language’s own words and the names already in your program, and needs nothing installed.

An equation too wide for the column breaks after a relation rather than in the middle of a term — and the pieces stay one formula to edit, not three.

A Hebrew word in the middle of an equation is a right-to-left run inside a left-to-right one — the case everything else gets wrong, down to which end the colon lands on.

993 of them, found by name in the same search as everything else — no panel of your own to hunt through. A symbol whose name you know is one search away.

Search for a command and, beside the sentence explaining it, a small document does it — on real text, before you run anything. Under that, every way of reaching it.

Mark parts of the document as belonging to a version — the one with the solutions and the one without — and choose which version prints. One file, not two that drift apart.

Give a version a name before a rewrite. Later, see exactly which words changed — marked in the prose itself, not as a wall of file differences.

Chapters of a thesis kept as one object: a class, a face and margins applied to all of them at once, numbering that runs across the whole thing, and one export for the lot.

Define \R once and write \R for the rest of the paper. The editor draws it, the search finds it and the LaTeX export writes it — and the definition travels inside the document.

Mark a term wherever you use it and the index lists every page it appears on — the pages it will really print on, not an estimate. The same for a list of the symbols you have defined.

Pictures, drawings and your own definitions all travel inside the .mfld — sending somebody a document sends them the whole document, not a file that asks for four others.

A paper written in another structured editor opens beside a .mfld — layouts, lists, formulas, tables, notes, cross-references and figures all come across. Whatever cannot is reported by name rather than quietly dropped.