What is I/O?
Input/Output
I/O (Input/Output) is the system's data exchange with the outside world.
Definition and Word Origin
Keyboard typing, downloaded file, result printed on the screen: All are I/O operations. The system talks to the outside world through this channel. It is like the senses and hands of the computer.
How to Know and Use in Daily Life?
Keyboard: Text entry.
Network: File download.
Screen: Don't show results.
Technical Depth and Architecture
Concepts:
Blocking: Don't wait until the process is finished.
Non-blocking: Don't wait, let me know when the results come.
Buffer: Intermediate tank that balances the speed difference.
Bottleneck: The slowest link slows down the entire line, usually disk or network.
File reading example:
const veri = await fs.readFile("not.txt", "utf8");This line does not wait until the file arrives, other work continues. It continues when the result is ready.
Use in Different Disciplines
Person: Eye-ear input, speech output.
Restaurant: Order entry, service exit.
Factory: Raw material input, product output.
Questions and answers
Why is I/O a bottleneck?
Processor is fast, disk and network are slow. When the data does not catch up, the system waits and this is where the bottleneck occurs.
What is blocking?
It is a call that waits until the result comes. It crashes the interface, wastes work on the server.
How to speed it up?
With cache, batch read and asynchronous call. It is measured first, then the slowest ring is corrected.
What does async have to do with it?
It is another way of doing work while waiting. A lot of work can be done with a single thread.
Related terms
Related tools
This explanation was written in plain language for TreScout with AI and machine-translated from the Turkish original · the Turkish version prevails. If something looks wrong or missing, write to hello@trescout.com. Read in Turkish →