Create a backup of your configuration

Config Backup: creates a zip file with your configuration settings
Config + Graphs Backup: adds the data used to generate the statistical graphs (roughly +15MB)

In almost cases one of the two options above is what you really want. The two options below create potentially significantly larger backup files (read - it takes much longer to create the backup and much longer to restore) and unless you know that you definitely do need that additionally data, you should likely stick with one of the two options above.

Full Backup: adds on top of all that the replay / heatmap data
Skystats DB Backup: creates a SQL dump of the Skystats PostgreSQL database

Depending on the amount of historic replay / heatmap data you have, a Full Backup can take a signficant amount of time and result in a very large archive to be downloaded. If you want to limit the data retained on disk, you can use MAX_GLOBE_HISTORY=365 in the environment variables on the expert page to only retain a year of data, this setting will not impact graph data.