Operating system

Operating system

1. Definition

   • is a software system that manages
     • hardware
       • Collection of physical elements
         • that constitues
           • A Computyer system
             • It can be
               • Input
               • output
               • memory allocation
     • sorftware
       • Set of a machine-readable instructions
         • that direct
           • a computer processor
             • for
               • specific operations

2. Examples

   • Android
   • Windows Phone
   • BlackBerry
   • iOS

3. Function

   • it provides
     • a stable system way
       • for
         • applications
           • to
             • deal with the hardware without having to know al details
               • of
                 • HARDWARE

4. Application code

   • Usually
     • executed
       • by
         • Hardware
           • And make frequently systerm calls
   • cellular phone
   • video games console

5. Types

   • TASKING
     • Single
       • Can only run one program at time
     • Multi
       • Can run more than one program at time
   • USERS
     • Single
       • have to facilities to distinguish users
         • but
           • allow multiple programs to run in tandem,
     • Multi
       • extends the basic concepts of multi tasking with facillities that identify processes an resources
   • DISTRIBUTED
     • Manages
       • group of ditinguish computers and make them opeer to be a single computer
   • TEMPLATED
     • In an OS
       • distributed and cloud
         • computing context
           • templating
             • refers to creat a single virtual machine
               • image a guest of operating system
   • EMBEDED
     • are designed for operate small machines
       • like PDAs
   • REAL TIME
     • guarantees to process
       • events or datas within a certain short amount of time
   • LIBRARY
     • networking

6. Developments

   • first generation of a computer (1950)
   • a discrete aperarence of OS (1950)
   • changes in informatic fields appear unix and multics in (1960-1970)
   • appear big scales and chips and starting the augment of computers appear -mac OS & -ms dos (1980-1990)