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Cyber Resilience Act Experience it live.

What the CRA requires of manufacturers: checking whether it applies, meeting reporting deadlines, keeping software bills of materials.

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Cyber Resilience Act: applicability check

A product runs through the five CRA checks (digital product, operator, EU market, making available, cut-off date) and either drops out or gets its role: manufacturer, importer, distributor or deemed manufacturer. Plus product class with conformity route (module A, B + C, H, certificate) and timeline: reporting since 11 Sep 2026 even for existing units, full application from 11 Dec 2027. Ten examples from mechanical engineering.

Betriebliche WeiterbildungTry it

CRA quick check

Answer 18 Cyber Resilience Act questions with yes, partly, no or open: a maturity ring shows product and role, reporting check and evidence, the live evaluation rates the state (structured, building up, starting point), caps it when core structures are missing and names the top 3 gaps and next steps. Product class separately; copy or print the result.

Betriebliche WeiterbildungTry it

CRA reporting deadlines: the reporting clock

Reporting obligations under Art. 14 of the Cyber Resilience Act in four machinery cases: register a notice, assess it, decide on reportability. From awareness the clock runs: early warning within 24 h, notification within 72 h, weekends included; plus the internal reporting process.

Betriebliche WeiterbildungTry it

SBOM for a gate operator (3D)

A gate operator as a software bill of materials in 3D: dependency tree with direct and transitive libraries, five releases and 58 customer installations. A headline reports a vulnerability and the 24-hour clock starts. Without an SBOM every customer counts as affected, with an SBOM five installations light up.

Betriebliche WeiterbildungTry it

PHP2Shell: a use-after-free bug in the PHP core

A concept model of the PHP2Shell use-after-free bugs: a PHP worker shares its memory across requests. When one request runs out of memory and aborts, a global pointer keeps pointing into freed memory; the next request reuses those cells, and the dangling pointer leaks a stranger's password into the PHPSESSID cookie. Step through it and switch the patch on and off.

Computer scienceTry it

Collections

More collections. Curated by us.

Project management

Planning and steering projects: the iron triangle, stakeholders, network diagrams, earned value, schedule risk, team size, Kanban and waterfall against Scrum.

8 appsOpen collection

Explizit oder rekursiv: die Folgentreppe

Financial mathematics

From sequences to loans: arithmetic and geometric growth, savings plans, annuities, compounding within the year and perpetuities.

11 appsOpen collection

Archaeology

Reading the traces: burial mounds in section, radiocarbon dating, settlements in the landscape and the tomb of Tutankhamun.

5 appsOpen collection

Warum ist ein Roboterarm so schwer zu steuern? (3D)

Roboterhand im Raum — sechs Achsen, acht Lösungen (3D)

Roboterarm mit Gewicht — Haltemoment, Regelung, Kopplung (3D)

Robotics

Why robot arms are heavy, how six axes guide a hand and how control holds the load.

4 appsOpen collection

Relationales Modell: ein Topf voller Tabellen

Schlüssel zur Wohnung: Primär- und Fremdschlüssel

SQL-Fließband: Die Maschine liest anders

SQL and databases

Tables, keys, joins, groups and subqueries you can touch: how a database really reads.

7 appsOpen collection

Zauberkasten KI: ein Funke, sechs Kräfte

Das Wortorakel: wie ein Sprachmodell schreibt

Die schöne Fassade: Warum KI-Antworten so überzeugend wirken

Zauberspruch-Werkstatt: gut mit KI sprechen

Understanding AI

Generative AI in strong images: what it can do, how it writes, why it convinces, how to use it well and where to take care.

7 appsOpen collection

Automotive technology

Engine, brakes, high voltage, CAN bus and chassis: technology and diagnostics of the modern vehicle.

9 appsOpen collection

Platz für Bäume: Altstadt Reutlingen (3D)

Asphalt raus: Entsiegelung Innenstadt (3D)

Urban climate

Heat in the city centre: heat islands, shade, trees and unsealing, using the old town of Reutlingen as an example.

5 appsOpen collection

Dark-Patterns-Detektor: Abofallen im Online-Shop

Verständlichkeits-Werkstatt: ein Verbraucherbrief in fünf Schritten

Consumer knowledge

Reading the small print, spotting subscription traps, placing risk figures and making texts understandable.

4 appsOpen collection

Differential equations

From equation to curve: initial values, linear equations, substitution and the worlds in which they apply.

7 appsOpen collection

Schwerpunkt-Brett: der Mittelwert als Gleichgewicht

Statistics from the start

Mean, median, mode, box plot and levels of measurement: descriptive statistics to try out.

9 appsOpen collection

Koordinaten nach Descartes: Geometrie wird Algebra (3D)

Vectors and matrices

From coordinates to the inverse: vectors, dot and cross products, linear equations and matrices in pictures.

12 appsOpen collection

Vier Wege zu fertigen: Baustelle, Werkstatt, Reihe, Fluss (3D)

Verschwendung finden: sieben Arten in der Fertigung (3D)

Los oder One-Piece-Flow: zehn Stück, zwei Wege (3D)

Wertstromkarte TIM Corp.: vom Ist- zum Soll-Zustand

Factory and production

Production principles, waste, one-piece flow, value streams, bills of materials and routing: how a factory is organised.

6 appsOpen collection

Brüche multiplizieren mit kreuzweisem Kürzen

Brüche dividieren: Wie oft passt es hinein?

Fractions

Reducing, common denominators, multiplying, dividing and mixed numbers: fractions step by step.

7 appsOpen collection

Zagiers Windmühlen: Primzahlen als Summe zweier Quadrate

Museumswächter: Warum n/3 Wachen reichen

From Erdős' Book

Proofs of special beauty to touch: Zagier's windmills, the museum guards and Buffon's needle.

3 appsOpen collection

Gezupfte Saite: Wo man zupft, bestimmt den Klang

Ein Radio aus Mathematik: Koeffizienten herausfiltern

Fourier to hear and see

How oscillations break down: coefficients, symmetry, phasor chains, the Gibbs phenomenon and the plucked string.

7 appsOpen collection

Understanding programming

What happens inside the machine: objects, methods, operators, slicing and sorting in Python, visible step by step.

9 appsOpen collection

Benz Patent-Motorwagen 1886 — der Viertakt im Schnitt (3D)

Erster Dieselmotor 1897 — Zündung durch Verdichtung (3D)

Masterpieces of engineering

From the Patent Motor Car to the Z3: famous machines and experiments cut open in 3D.

11 appsOpen collection

Understanding and playing music

Keyboard, intervals, scales, chords, the circle of fifths and groove: music theory you hear and play.

9 appsOpen collection

Klanglabor: Synthesizer, Sampler, Sounddesign

Sound & sound design

How sound is made and shaped: synthesizers and samplers, envelopes and overtones, waveforms and timbre, voice and orchestra, room acoustics and sound scenography — all audible in your browser.

16 appsOpen collection

Scenography

Staging space, sight, light, sound and paths: visitor flows, showcase lighting, room acoustics, sound islands, projection mapping and the pavilions of world expos to try out.

15 appsOpen collection

Die Ebene ist nicht fünffärbbar (Hadwiger–Nelson)

Gaußscher Graben — kein Weg ins Unendliche

Open Problems, Solved by AI

Mathematical questions open for decades, for which an AI model proposed solutions in 2026, as interactive apps: understand the problem, experience the result.

32 appsOpen collection

AI and Machine Learning

From neurons and gradients to transformers, RLHF and agents: machine learning you can touch.

44 appsOpen collection

Molecular Biology

DNA, replication, transcription, translation and cell division as explorable 3D models.

24 appsOpen collection

Art and Architecture

Perspective, ornament, structure and space: how art and architecture work with mathematics.

21 appsOpen collection

Autonome Verkehre in logistischen Systemen (3D)

Modern Logistics

Hyperloop, autonomous vehicles, warehouses and conveyors: logistics as interactive simulation.

17 appsOpen collection

Medicine and Anatomy

Heart, eye, voice, skeleton and nerves: the human body in 3D, layer by layer.

10 appsOpen collection

Statistical Traps

Monty Hall, Simpson, Berkson and base rates: where intuition fails us with numbers.

14 appsOpen collection

Schwarzes Loch — Gravitationslinse und Schatten (3D)

Astronomy and Cosmos

Planets, stars, black holes and space probes: the cosmos to explore.

10 appsOpen collection

Kanalrhodopsin: ein Lichtschalter für Nervenzellen

Optogenetik: Zelltypen, Maus und Sehhilfe

Neutrinos: Geisterteilchen, die durch die Erde fliegen

Nobel Prizes 2026

Light switches for nerve cells, a telescope made of ice, mirror-image chemistry and interest rates: the 2026 Nobel Prizes to try out.

8 appsOpen collection

Asch-Linien: Die Mehrheit irrt mit Absicht

Zuschauer-Effekt: Alle warten, keiner hilft

Deceived in the Lab

Planted participants, smoke in the room, one dollar for a lie and experimenters who are themselves the subjects: famous social psychology experiments to try yourself.

5 appsOpen collection