This book contains interesting 100 hands-on C# utility programs. These 100 programs are very essential and useful to C# developers. This book focuses only on the system side, utilities, and multimedia programs. This book provides the programs based on the concept of WMI, windows registry, drawing, and windows API’s. This book is logically divided into four parts. Part I start with C# fundamental programs; here I focus some basic programs like string handling, arrays, etc. Part II has intermediate level programs; here I focus WMI and windows registry handling programs. These kinds of programs required some programming knowledge. Part III begins with advanced programs like compression, security, media player etc. Part IV shares the research ideas and methods.