What does the 1% transaction fee for Shopify POS Pro cover?

[Opsmh]

I would like to figure out the exact costs that i am going to pay. 

I am planning to move my brick & mortar business to Shopify POS and then also benifit from the online platform to expand my sales. 

Planning to use POS pro $89 and Shopify $49 so that fees are clear

What type of transactions are included in the 1% transaction fees. 

In my brick and mortar store i do alot of small cash sales and mostly online transfer sales. Do i pay for these transactions also in the 1%.