Zusammenfassung der Ressource
Operating systems
- user interface
- Operating
systems need
to provide a
means of
communicating
with them.
- This means
making it possible
for the user to
issue commands.
- The user
interface is the
way in which
users interact
with computer
hardware.
- Can be either
Graphical (GUI)
or Command
Line.
- Multi-tasking
- Most systems
commonly have
several programs
loaded into memory at
the same time.
- The operating
system will also
be running lots
of background
tasks just to
manage the
computer itself.
- A processor
can only
execute one
instruction
at a time
(assuming it
only has one
core).
- The operating system
has to mange all the
programs running to
make sure each one
gets enough
processor time.
- Security
- Operating systems
usually allow the
authentication of users,
i.e. they can be set up to
check that users are who
they say they are.
- This normally involves
users having user ids
and password.
- Operating systems also
handle file privileges,
these are right assigned to
users and group.
- This control who can
read / write and execute
files.
- Peripheral Management
- Peripherals are any
computer hardware
components that are
not part of the CPU i.e.
Input, Output or
Storage devices.
- A function of the
operating system is to
manage these devices.
- The
operating
system may
need to find /
ask user to
install
suitable
drivers for the
device to
work.
- These drivers allows an
operating system to
communicate with the
device.
- Memory Management
- When a program
is running it must
be in the
computer’s main
memory (RAM).
The main
memory has a
finite size.
- The operating system
must manage where in
memory the programs
will go.
- The operating system tracks where programs
and data are at any time to make efficient use
of the space in memory and to make sure
nothing gets overwritten by something else.
- As a program is finished it can be
removed from memory and as as
new ones are run they will be
loaded into memory.