1 | initial version |

Hi @omoplata!

This kind of question is fine either here or on `sage-support`

-- which you use is just a matter of your preference.

Practically speaking, there is no difference between the two formats -- they both create a variable `x`

. I think the different usage has to do with the fact that `var`

both creates and *returns* the variable. So if you type

```
var('x')
```

you will get output

```
x
```

If you type

```
x = var('x')
```

then you are assigning the return value of `var('x')`

to something (`x`

in this case), and hence nothing is printed. This is just like the difference between

```
sage: 1 + 1
2
```

and

```
sage: w = 1 + 1
<nothing printed here>
```

An amusing side note is that you can make your code more confusing by assigning the return value of `var('x')`

to a *different* variable:

```
t = var('x')
```

Then you can use the variable `t`

, but it will always be printed as `x`

.

```
sage: y = t^2 + t + 1
sage: y
x^2 + x + 1
```

I wouldn't really recommend using this ;)

2 | No.2 Revision |

Hi @omoplata!

This kind of question is fine either here or on `sage-support`

-- which you use is just a matter of your preference.

Practically speaking, there is no difference between the two formats -- they both create a variable `x`

. I think the different usage has to do with the fact that `var`

both creates and *returns* the variable. So if you type

```
var('x')
```

you will get output

```
x
```

If you type

```
x = var('x')
```

then you are assigning the return value of `var('x')`

to something (`x`

in this case), and hence nothing is printed. This is just like the difference between

```
sage: 1 + 1
2
```

and

```
sage: w = 1 + 1
<nothing printed here>
```

An amusing side note is that you can make your code more confusing by assigning the return value of `var('x')`

to a *different* variable:

```
t = var('x')
```

Then you can use the variable `t`

, but it will always be printed as `x`

.

```
sage: y = t^2 + t + 1
sage: y
x^2 + x + 1
```

I wouldn't really recommend using this ;)

**Edit**: Oh, I see that this question has been answered numerous times since I started composing my overly-long answer; sorry!

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