This document discusses using convolutional neural networks (CNNs) for brain tumor detection. CNNs have convolutional, pooling, and dense layers that can extract features from medical images like MRIs. The document focuses on a CNN model to classify brain images as either containing a tumor or being healthy. The model is trained on a dataset of 259 brain tumor images and 20 healthy images from Kaggle, with data augmentation used to address class imbalance. The CNN contains convolution, pooling, dropout and dense layers with rectified linear unit activation. It aims to accurately detect tumors in brain MRI images.