bündeln
to pool
To combine forces, interests, resources, or efforts and align them toward a common goal.
Um das Projekt zu retten, müssen wir unsere Kräfte bündeln.
To save the project, we have to pool our strengths.

to bundle
Loading your saved state.
to pool
To combine forces, interests, resources, or efforts and align them toward a common goal.
Um das Projekt zu retten, müssen wir unsere Kräfte bündeln.
To save the project, we have to pool our strengths.

The verb 'bündeln' (to bundle) is derived directly from the noun 'das Bündel' (bundle). A bundle is a number of things tied together. So 'bündeln' literally means to make something into a bundle.
Für das Lagerfeuer bündelte er trockene Äste.
For the campfire, he bundled dry branches.
'Bündeln' (to bundle) is always used with an accusative object. So you have to state what is being bundled.
Die Firma bündelt ihre Marketingaktivitäten in einer neuen Abteilung.
The company is bundling its marketing activities in a new department.
In the figurative meaning, 'bündeln' (to pool) is often used with abstract nouns. Typical combinations are 'Kräfte bündeln' (to pool forces), 'Energien bündeln' (to focus energies), 'Ressourcen bündeln' (to pool resources), or 'Kompetenzen bündeln' (to pool expertise).
Wir sollten unsere Kompetenzen bündeln, um die beste Lösung zu finden.
We should pool our expertise to find the best solution.
In the literal meaning, 'bündeln' (to bundle) is used with concrete objects. Common combinations are 'Holz bündeln' (to bundle wood), 'Kabel bündeln' (to bundle cables), or 'Kräuter bündeln' (to bundle herbs).
Der Gärtner bündelte die frisch geschnittenen Kräuter.
The gardener bundled the freshly cut herbs.
You can recognize the physical meaning from words like 'Licht' (light), 'Strahlen' (rays), or 'Linse' (lens) in the sentence. In this context, 'bündeln' (to focus) describes the focusing of energy or particles.
Ein Hohlspiegel kann parallel einfallende Lichtstrahlen bündeln.
A concave mirror can focus parallel incoming light rays.
to collect / gather
'sammeln' and 'bündeln' have in common that individual things come together. 'sammeln' mainly means that you gather things, information, or experiences. 'bündeln' means more strongly that you organize and combine these individual parts, often directing them toward a goal. With forces, interests, or tasks, 'bündeln' often sounds more precise. With individual objects or pieces of information, 'sammeln' is usually more neutral and simpler.

Heute bündelt Paula in der Schule die Ideen der Gruppe für das Projekt.
Today at school, Paula is pooling the group's ideas for the project.
In der Küche sammelt die Chefin alle Bestelllisten für das Wochenende.
In the kitchen, the manager collects all the order lists for the weekend.