Command notations

You will see this notation in many places.

When reading command documentation, you will see notations representing various conditions. Not every command must be copy-pasted, some needs to change values depending on what do you want.

>>> Input

In some interactive shells, you will have this symbol (>>>) at the start of your cursor, it means the software is waiting for user input. In documentation, it means something you should write.

>>> print("Hello world")    # This is an input
Hello world                 # This is an output

It can also be like > or $.

<Placeholder>

Represents a value for which you must supply a value.

For example:

python my_script.py <file>

You need to fill the place where <file> is with your own value.

Example

python my_script.py my_file.txt

[Optional]

Represents a value for which you can supply a value or leave empty.

For example:

python my_script.py [file]

It's not necessary to put something in [file].

Example

python my_script.py my_file.txt
python my_script.py

{Mutually|Exclusive|Values}

Represents a placeholder for which you must select one item of that list.

For example:

command {value1|value2|value3}

You should select only one value in that placeholder.

Example

command value1
command value2
command value3

--option

Some commands let you add options (or flags) to change behavior. It can be with 1 dash (-) or 2 (--). Every command has their own way.

The --help or -h flag is very common in almost all commands. It shows information about the usage of a command. Use it everywhere you can.

python --help