What is the difference between a 'parable' and a 'fable'?

Fables tends to have animals as their main characters whereas parables typically have people as the main characters. Both fables and parables are short stories that typically teach a lesson.

https://www.writersdigest.com/write-better-fiction/fable-vs-parable-vs-allegory-grammar-rules

Parables and fables are both short stories designed to teach lessons, but they differ in style, characters, and depth. Parables use realistic human characters and everyday situations to convey moral or spiritual truths. They're often found in religious or philosophical texts and aim to provoke reflection. The message is usually subtle and open to interpretation.

Fables, on the other hand, feature animals or objects with human traits and are more whimsical or fantastical. They deliver clear, practical morals, often stated outright at the end. Fables are common in folklore and children's literature, with Aesop's tales being the most famous examples.

Parables = realistic, reflective, spiritual Fables = imaginative, direct, moralistic.

https://www.writersdigest.com/write-better-fiction/fable-vs-parable-vs-allegory-grammar-rules