Oracle products follow a custom release-numbering and -naming convention.
The "c" in the current release, Oracle Database 23c, stands for "Cloud". Previous releases (e.g. Oracle Database 10g and Oracle9i Database) have used suffixes of "g" and "i" which stand for "Grid" and "Internet" respectively.
Prior to the release of Oracle8i Database, no suffixes featured in Oracle Database naming conventions.
Oracle Database releases are released in version and version_full releases.
The version release is designated in the form major release version.0.0.0.0. The major release version is based on the last two digits of the year in which an Oracle Database version is released for the first time. For example, the Oracle Database version released for the first time in the year 2018 has the major release version of 18, and thus its version release is 18.0.0.0.0.
The version_full release is an update of a version release and is designated based on the major release version, the quarterly release update version (Update), and the quarterly release update revision version (Revision).
Oracle Database release numbering has used the following codes:
First numeral: This numeral indicates the major release version. It also denotes the last two digits of the year in which the Oracle Database version was released for the first time.
Second numeral: This numeral indicates the release update version (Update, or RU).
Third numeral: This numeral indicates the release update revision version (Revision, or RUR).
Fourth numeral: This numeral is reserved for future use. Currently it is always set to 0.
Fifth numeral: Although only the first three fields are commonly used, the fifth field can show a numerical value that redundantly clarifies the release date of a release update (RU), such as 19.7.0.0.200414.
