what does 1st class mail mean

what does 1st class mail mean First-Class Mail is a category of postal service offered by USPS that includes lightweight items such as letters, postcards, and small packages. It is one of the most affordable and widely used mailing options for sending non-urgent mail domestically. First-Class Mail typically delivers within 1-3 business days, making it a fast option for everyday communications. USPS First-Class Mail offers delivery confirmation and is also used for shipping small parcels weighing up to 13 ounces. It’s an economical choice for sending lightweight items.