A windows system is a GUI operating system that allows multiple applications to be run at the same time. Its name comes from the window UI element that can be movable, hidden and maximized.
The operating system uses a layered architecture. The kernel is responsible for NT synchronization, process management and memory protection.
Graphical User Interface (GUI)
GUI uses windows, icons, menus and pointers to display information and user controls. It provides graphical representations of data and commands instead of text, and it is used on mobile devices as well as personal computers and laptops. Users interact with the interface through a pointing device such as a mouse or trackball and, in some cases, with a stylus on touchscreens.
A GUI consists of a rectangular area of the screen where an application is displayed, along with toolbars and other elements that support software functions. These are arranged in a consistent way to make it easy for users to navigate and understand the software.
A GUI must have clear and easy-to-understand labels for each element and provide feedback on errors. In addition, each piece of the GUI should have a purpose. This helps users know which command to execute and how to do it. The tutorials in the Net Express book include an example of creating a GUI front-end for a service created with Net Express.
Memory Management
Memory Management is the functionality of an OS that takes control of primary memory and coordinates its use by processes. It determines what processes get what amount of memory and moves them back and forth between main memory and disk during execution.
Windows NT uses a page-based memory management scheme that divides memory into equal chunks called pages. Each page is 4096 bytes (4K) in size. Everything in a process, code, resources, files, dynamic memory, and so on, is implemented by one of these pages.
Address translation breaks a virtual address into three offsets to index into a page of memory. Each page is then mapped to a frame of memory in the main memory or in the page file on disk. The page-map table keeps track of the relation between a process’s pages and its frames, as well as other important information about the memory location. Each page-table entry has a segment number, the size of the segment, and a link to a corresponding memory location in the main memory or the page file.
Process Management
Each program running on an operating system is assigned a unique identifier known as the process ID. The process identifier contains important information about the program, such as its memory and CPU usage. Some processes are “foreground” and require user interaction, while others are background or system processes. These are usually executed after a foreground program.
Windows stores a variety of information about each process, including its priority, status, memory usage, and power throttling status. You can view this information by opening the Task Manager or by using Sysinternals tools.
Each process has a number of handles that represent various resources, such as files, registry keys, and windows. It also has threads that share processor time. The amount of CPU resources the process uses is displayed as a percentage. A counter is also shown to indicate how much CPU resources are idling. The system idle process is not a real counter, but rather a function within the WinTasks display that indicates how many percent of CPU resources are idling.
Security
Every piece of software installed on a system adds to its risk of compromise, so it is important to install only the required programs. Unneeded software can leave behind components that attackers may exploit later to gain access to critical processes or to the device itself.
The Windows operating system provides a number of security measures to ensure its integrity. These include built-in services that check the integrity of system files responsible for normal computer performance. If these files are changed, the system will alert the user with a notification.
Microsoft also provides other security technologies to protect the integrity of hardware and firmware. These include a secure boot process and protection against malware attacks on the UEFI. Additionally, it supports a kernel-level block policy that prevents non-Microsoft drivers from running on the Windows kernel. This prevents attackers from exploiting kernel drivers to gain access to the system. Furthermore, it also offers options for encrypting data to prevent unauthorized access to sensitive information.