Over a long period generative models such as HMMs are state-of-the-art in NLP/SLP. HMMs are successful in various domains. Speech Recognition, PoS-tagging, G2P, TTS etc.... HMMs have some limitations that recent statistical modeling approaches overcome. These statistical learning algorithms can be grouped under Discriminative Modeling or as in Speech Recognition under Discriminative Training. One of those algorithms is the Conditional Random Field approach. The talk gives an overview what a Conditional Random Field is and the difference between Generative Models and Discriminative Models.