Basically, there are four types of machine learning algorithms.
1- Supervised Learning Algorithms-
In supervised learning, values of features and labels or classes are given.
Further, Supervised learning algorithms are of two types.
1.1- Regression-
In regression numerical values are predicted.
1.2-Classification
In classification, labels are predicted.
2-Unsupervised Learning Algorithms
In unsupervised learning, instances have not any labels. These types of algorithms are used to find out patterns inside data and reduce features of data set.
3-Semisupervised –
It has data set in which some instances has labels and some instances has not any labels.
4- Reinforcement Learning-
Reinforcement learning is a different kind of algorithm and widely used in Robotics.
To explain classification problem, I have used 9 instances of Iris data set.
To see the detail please watch the video.