ELI5: Explain Like I'm 5

standard streams

Imagine you are playing with some water. You have a big bucket which contains water, and you also have some empty cups. You can pour the water from the bucket into the cups and then drink it or use it to water plants.

Now, let's look at the computer. A program can also take input and output information. Instead of water, we have data that programs use. Standard streams are like the cups and bucket in the water example, but instead of water, we have data that goes to and from programs.

There are three standard streams: standard input (stdin), standard output (stdout), and standard error (stderr). Standard input is how a program takes input from you (like when you type something into the terminal). Standard output is how a program gives you output (like when you see text printed to the terminal). Standard error is where a program sends error messages (like when there is a problem with the program).

Just like with the cups and bucket, we can use these standard streams to transfer information between programs. For example, we can take the output from one program and use it as input for another program.

So, the standard streams are a way for programs to talk to each other and to you, like pouring water from a bucket into a cup to drink or use for other purposes.
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