Looking up...
The content of the book is very interesting.
Der Inhalt des Buches ist sehr interessant.
Inhalt (von etwas, z. B. Buch, Film, Website)
The website's content is updated daily.
Der Inhalt der Website wird täglich aktualisiert.
Can refer to written, visual, or auditory material.
zufrieden (mit einer Situation oder einem Ergebnis)
She was content with her life.
Sie war mit ihrem Leben zufrieden.
Often used with 'with' (mit).
Inhalt (von Behältern, z. B. Koffer, Glas)
The contents of the suitcase were scattered everywhere.
Der Inhalt des Koffers lag überall verstreut.
Plural form 'contents' is common in this sense.
Remember: 'content' as an adjective (zufrieden) is always used with a form of 'to be' (e.g., 'I am content'). As a noun (Inhalt), it stands alone or is modified (e.g., 'the content of the box').
From Latin *contentus* (satisfied), past participle of *continere* (to hold together, contain). The sense of 'material within something' emerged in Middle English.
As an adjective, 'content' is used predicatively (after a verb like 'be') and takes 'with'. As a noun, it can be uncountable (general sense) or countable (specific items).