This is a first course on computer processing of speech signals for undergraduate students in electrical engineering and computer science. Both theoretical issues and practical problems will be discussed, and both fundamental concepts and research topics will be emphasized. The viewpoints will be centralized on the vision of spoken language processing under-network environment. Part I: Fundamental Topics 1.Introduction 5.Acoustic Modeling 2.Basic Concepts in Speech Recognition 6.Language Modeling 3.Research Roadmap in this Area 7.Speech Signals and Front-end Processing 4.More about Hidden Markov Models (HMM) 8.Linguistic Decoding and Search Algorithm Part II: Research Topics 1.Speaker Variabilities: Adaptation and Recognition 2.Latent Semantic Analysis for Linguistic Processing 3.Voice-based Information Retrieval 4.Robustness for Acoustic Environment 5.Spoken Document Understanding and Organization 6.Some Fundamental Problem-solving Approaches 7.Keyword Spotting and Utterance Verification 8.Spoken Dialogues 9. Distributed Speech Recognition and Wireless Environment