A Flora is a book or other work which describes the plant species occurring in an area or time period, often with the aim of allowing identification. The term is usually capitalized to distinguish it from the use of "flora" to mean the plants rather than their descriptions. Some classic and modern Floras are listed below.

Traditionally Floras are books, but some are now published on CD-ROM or websites. The area that a Flora covers can be either geographically or politically defined. Floras usually require some specialist botanical knowledge to use with any effectiveness.

A Flora often contains diagnostic keys. Often these are dichotomous keys, which require the user to repeatedly examine a plant, and decide which one of two alternatives given in the Flora best applies to the plant.

Floras produced at a local or regional level rarely contain identification keys. Instead they aim to impart more detailed understanding of the local status and distribution of that area's plants. Maps showing species distribution may be included, and nowadays are computer-generated from biological databases. Specific reference may be made to new arrivals and historic records in order to impart understanding of the changes in an area's vegetation over time.