8086 microprocessor

i am learning 8086 microprocessor.i am really confused regarding the i/o interfacing concept.i hv searches in net,books but could not find the answer.my question is..why we use 8255 for i/o interfacing?cant we directly connect the device to 8086?what is the need of connecting 8255?plz help

The 8086 does not have any latched output pins.
The pins change millions of times per second to access memory
or I/O chips such as the 8255.
That is normal for a microprocessor, only micro-controllers
such as the 8051 have latched output ports built in.

The 8255 is needed to latch an output, that is,
to keep it stable.

8086 is a microprocessor with only a CPU. It does not have a GPIO controller. So thats the reason you need to have an external IO controller like 8255.