# Combining Dataframes

## Why combine dataframes

If you have mulitple dataframes, it can be useful to combine them into a single dataframe. This may be because they share a key, and you want to analyze the data together, or that the dataframes are each pieces of a larger dataset that were split up for performance reasons, or something else entirely. Mito has tools that make combining these dataframes together incredibly easy!

## Different ways to combine data:

{% hint style="info" %}
Looking to include use VLOOKUP like in Excel? In Mito, you can use the VLOOKUP formula just like Excel. See the formula documentation [here](https://docs.trymito.io/interacting-with-your-data/mito-spreadsheet-formulas#vlookup). 
{% endhint %}

Merge combines dataframes based on values in shared columns (like a VLOOKUP in Excel):

{% content-ref url="combining-dataframes/merging-datasets-together" %}
[merging-datasets-together](https://docs.trymito.io/how-to/combining-dataframes/merging-datasets-together)
{% endcontent-ref %}

Concat is used to stack two dataframes on top of eachother:

{% content-ref url="combining-dataframes/concatenate-dataframes" %}
[concatenate-dataframes](https://docs.trymito.io/how-to/combining-dataframes/concatenate-dataframes)
{% endcontent-ref %}

Dataframe difference calculates the difference between two dataframes:

{% content-ref url="combining-dataframes/anti-merge-unique" %}
[anti-merge-unique](https://docs.trymito.io/how-to/combining-dataframes/anti-merge-unique)
{% endcontent-ref %}