---

Batch operating systems are designed to execute batches of jobs without user interaction. Users prepare their tasks offline (e.g., on punch cards) and submit them to a computer operator. Jobs with similar requirements are grouped and processed together to optimize performance.

• Lack of interaction between user and job.
• Jobs are processed sequentially in batches.
• Designed for efficiency in executing repetitive tasks.

• Limited user interaction.
• CPUs may remain idle due to slow I/O devices.
• Difficult to assign priorities to specific jobs.

---

Time-sharing systems allow multiple users at different terminals to interact with a single computer simultaneously. Each user gets a time slice of CPU, ensuring quick responses. This system minimizes idle time and maximizes user interaction.

• Quick response times.
• Avoids duplication of software.
• Efficient CPU utilization.

• Reliability issues.
• Security and data integrity concerns.
• Requires robust data communication.

---

A distributed OS uses multiple processors across different systems, working together to execute tasks. These processors communicate through communication lines like high-speed buses or telephone lines.

• Enables resource sharing across systems.
• Facilitates faster data exchange via email or shared storage.
• Continues operations even if one site fails.
• Reduces delays in data processing.

• Loosely coupled systems used in cloud computing and distributed applications.

---

Embedded Operating Systems are specialized systems designed to manage hardware and software resources of embedded devices. These systems are task-specific and are optimized for efficiency, reliability, and speed. They typically execute a single task repeatedly for their entire lifetime, maintaining a strict schedule to meet time constraints.

---

• Perform a particular task repeatedly, often in a loop, throughout their operational lifespan.
• Designed to complete tasks within a specific time frame, ensuring they are fast enough to meet deadlines.
• Provide little to no user interaction. For example, a fully automatic washing machine operates independently after its program is set.
• Built to be highly efficient and reliable, with minimal hardware and power requirements.
• Embedded systems cannot be updated or upgraded, requiring them to be extremely robust and reliable from the outset.
• The operating system is lightweight and consumes minimal power, making it suitable for devices with limited resources.

---

• Easily adaptable for use across various hardware platforms.
• Executes tasks much faster than traditional operating systems.
• Operates effectively with minimal hardware resources.
• Delivers consistent and reliable operation.

---

• May lack advanced optimization for non-critical tasks.
• Significant effort is required to modify or customize the system.
• Tailoring the operating system to specific applications can be a lengthy process.

---

Real-time operating systems are designed for environments requiring immediate responses to inputs. These systems have strict time constraints and are commonly used for critical applications.

1. Hard Real-Time Systems

   • Guarantees completion of critical tasks on time.
   • Secondary storage is minimal or absent.
   • Used in weapon systems, air traffic control, and medical devices.

2. Soft Real-Time Systems

   • Critical tasks have priority over others but are less rigid.
   • Common in multimedia systems, virtual reality, and scientific exploration.

• Industrial control systems.
• Robotics and scientific experiments.
• Medical imaging and air traffic control.

---

Operating System Type	Features	Examples	Applications
Batch OS	Processes jobs in batches	IBM OS/360	Payroll systems, banks
Time-Sharing OS	Allows multiple users to interact simultaneously	UNIX	Online databases, office environments
Distributed OS	Uses multiple interconnected systems	Google Chrome OS	Cloud computing, resource sharing
Real-Time OS	Provides immediate responses to inputs	VxWorks, FreeRTOS	Robotics, industrial control
Embedded OS	Task-specific, optimized for speed and reliability	TinyOS, Contiki, FreeRTOS	Home appliances, medical devices, automotive