Scikit-learn is a free library in Python programming language for Machine Learning. It features various algorithms for major Machine Learning tasks such as classification, regression and clustering tasks including Linear regression, Decision Trees, Random forests, SVM, gradient boosting, k-means, and DBSCAN.
If you are interested to learn Machine Learning and implement ML projects, check out this Machine Learning Course by Intellipaat.
Also, watch this video on Machine learning with Scikit-Learn to get started:
