MongoDB is a popular NoSQL database known for its flexibility and scalability. Key commands in a MongoDB cheat sheet include:

• Insert Documents: db.collection.insertOne({}) or db.collection.insertMany([{}]).

• Query Documents: Use db.collection.find({}) to retrieve documents. Apply filters like {field: value}.

• Update Documents: db.collection.updateOne({filter}, { $set: { field: value } }) or db.collection.updateMany().

• Delete Documents: db.collection.deleteOne({}) or db.collection.deleteMany({}).

• Aggregation: Utilize db.collection.aggregate([{ $match: {} }, { $group: {} }]) for complex data operations.

• Indexing: Create indexes using db.collection.createIndex({ field: 1 }) to improve query performance.

These commands help manage and manipulate data efficiently in MongoDB.