USU (operating system) USU (operating system) USU linux (Bulgarian: УСУ; Учи Свободен с Убунту) is Bulgarian open source desktop operating system built around the KDE desktop environment and based on the popular free Linux distribution, Ubuntu. Usu can be downloaded in three flavours, Desktop, Mini and Netbook, each one with its own features and target audience. All of them can be downloaded for free, as Live CD/DVD ISO images, supporting 32-bit and 64-bit processors. The defult language is Bulgarian, but in installation it can be easy changed with F2 key. USU Desktop is created to be used as a learning tool, this edition
Hybrid kernel Hybrid kernel A hybrid kernel is an operating system kernel architecture that attempts to combine aspects and benefits of microkernel and monolithic kernel architectures used in computer operating systems. The traditional kernel categories are monolithic kernels and microkernels (with nanokernels and exokernels seen as more extreme versions of microkernels). The "hybrid" category is controversial, due to the similarity of hybrid kernels and ordinary monolithic kernels; the term has been dismissed by Linus Torvalds as simple marketing. The idea behind a hybrid kernel is to have a kernel structure similar to that of a microkernel, but to implement that structure in