die Rettung
rescue
The act of freeing someone or something from a dangerous situation or emergency.
Die Rettung der verunglückten Bergsteiger dauerte mehrere Stunden.
The rescue of the injured mountain climbers took several hours.

rescue
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rescue
The act of freeing someone or something from a dangerous situation or emergency.
Die Rettung der verunglückten Bergsteiger dauerte mehrere Stunden.
The rescue of the injured mountain climbers took several hours.

'Die Rettung' (rescue) is derived from the verb 'retten' (to rescue/save). The ending '-ung' forms a feminine noun that describes the action or result of the verb. This pattern is very common in German.
Die Rettung aus dem brennenden Haus war sehr gefährlich.
The rescue from the burning house was very dangerous.
You can recognize the meaning from the sentence structure. If someone 'die Rettung ruft' (calls the emergency services), it means the emergency medical service. If something 'die Rettung ist' (is the rescue/lifesaver), it means unexpected help. If it is about 'die Rettung von jemandem' (the rescue of someone), it means the rescue operation.
Jemand hat die Rettung gerufen.
Someone called the emergency services.
In an emergency, the phrase 'die Rettung rufen' (to call the emergency services) is used. This means alerting the medical emergency service (the ambulance) via the emergency number.
Nach dem Sturz hat er sofort die Rettung gerufen.
After the fall, he immediately called the emergency services.
In colloquial language, 'Rettung' (rescue/lifesaver) is often used emotionally and exaggeratedly for welcome help in an everyday but unpleasant situation.
Dieser Kaffee am Morgen ist meine Rettung!
This coffee in the morning is my lifesaver!
A common and somewhat dramatic phrase is 'jemandem zur Rettung eilen' (to rush to someone's rescue). It means coming quickly to help someone in an emergency.
Als das Kind ins Wasser fiel, eilte ihm ein Passant zur Rettung.
When the child fell into the water, a passerby rushed to his rescue.
help
'die Hilfe' and 'die Rettung' can both mean that someone gets support. 'Hilfe' is more general: someone makes something easier or supports someone with a problem. 'Rettung' is stronger and fits when someone or something is freed from danger, great distress, or a very difficult situation. Learners may confuse the words because a rescue is also a kind of help. But not every kind of help is a rescue. For normal tasks, you say 'Hilfe'; for danger or a serious emergency, 'Rettung' is more likely.

Nach dem Unfall kam die Rettung nach wenigen Minuten.
After the accident, the emergency services arrived within a few minutes.
Für die Bewerbung bat Maria ihre Freundin um Hilfe.
Maria asked her friend for help with the application.