
handeln
to act
To become active, do something, or carry out an action, often in response to a situation.
Angesichts der neuen Informationen müssen wir sofort handeln.
In view of the new information, we must act immediately.
to act / trade
Loading your saved state.

to act
To become active, do something, or carry out an action, often in response to a situation.
Angesichts der neuen Informationen müssen wir sofort handeln.
In view of the new information, we must act immediately.

to be
Describes what something or someone essentially is, or what a matter is about. A formal way of saying 'it is ...'.
Bei dem gefundenen Gegenstand handelt es sich um ein historisches Artefakt.
The found object is a historical artifact.

to be about
To describe the topic or content of something (e.g. a book, film, conversation).
Der Roman handelt von einer Familie während des Krieges.
The novel is about a family during the war.

to trade
To do business; to buy and sell goods.
Das Unternehmen handelt mit seltenen Gewürzen aus aller Welt.
The company trades in rare spices from all over the world.

to bargain
To negotiate over a price in order to lower it; to haggle.
Auf dem Flohmarkt konnte ich gut handeln und habe das Fahrrad 20 Euro billiger bekommen.
At the flea market I was able to bargain well and got the bike 20 euros cheaper.
The verb 'handeln' (to act / trade) is related to the noun 'die Hand' (hand). The basic idea is doing something with your hands, that is, becoming active or carrying something out.
Statt nur zu reden, sollten wir endlich handeln.
Instead of just talking, we should finally act.
'Handeln' does not directly mean 'to handle' in the sense of 'dealing with something.' 'Handeln' means 'to act' or 'to trade.' If you want to say 'I can handle it,' in German you often say 'Ich schaffe das' (I can manage it) or 'Ich kann damit umgehen' (I can deal with it).
Die Politiker müssen jetzt schnell handeln.
The politicians must act quickly now.
The meaning of 'handeln' depends strongly on the sentence structure. On its own, it means 'agieren' (to act). With 'von + dative', it describes a topic. With 'mit + dative', it means trading in goods. The reflexive form 'sich handeln um + accusative' identifies something.
Der Film handelt von einer wahren Geschichte.
The film is about a true story.
The expression 'es handelt sich um' is a fixed, impersonal construction with the accusative. The 'es' at the beginning is obligatory and cannot be replaced. This form is typical of formal, factual language.
Bei dem Anrufer handelte es sich um einen alten Freund.
The caller turned out to be an old friend.
The construction 'handeln von + dative' is almost always used to describe the content or topic of a book, film, conversation, or story.
Wovon handelt dein Lieblingsbuch?
What is your favorite book about?
When 'handeln' means 'Geschäfte machen' (to do business), it is always used with the preposition 'mit' and the dative. The object after 'mit' is the goods that are bought and sold.
Mein Onkel handelt mit gebrauchten Autos.
My uncle trades in used cars.
to do / make
Both words can express that someone takes action. „Machen“ is very general and often colloquial, while „handeln“ shows purposeful action, usually in response to a situation. If a specific but not yet defined action is meant, „machen“ is enough; for deliberate intervention, „handeln“ is a better fit.

Nach dem Unfall müssen wir jetzt schnell handeln.
After the accident, we have to act quickly now.
Nach dem Unfall müssen wir jetzt etwas machen.
After the accident, we have to do something now.