What are startup fundraising rounds?
Startups that choose to raise money from investors typically fundraise in rounds. A startup will usually first raise money for its idea from the friends and family of the founders. This is called the "Friends and Family Round". 

After this is the "Seed Round" in which the startup will raise capital from other investors, typically angel investors and venture capital firms.

Subsequent to the "Seed Round" is the "Series A". This capital is typically raised from venture capital and larger investors. 

Every subsequent fundraising round is the next letter in the alphabet: Series B, Series C, etc.