The aim of this book is to enhance knowledge of scientists, engineers and researchers regarding the advantages of principal component analysis in data analysis. Principal component analysis involves a statistical procedure which orthogonally transforms a set of possibly correlated observations into set of values of linearly uncorrelated variables called principal components. This book elucidates the uses of PCA in distinct fields like face recognition, and image and speech processing. The book also covers core concepts and novel techniques in data analysis and feature extraction.