Maven BOM (bill of materials) is a pattern for collectively managing the versions of multiple dependencies into your project.
For Maven based project which have several artifacts which don't follow single versioning schema vendors may supply recommended dependency via prepared dependency file in dependencyManagement
section.
Refer to official docs for example.
Common example of Maven BOM supplied by Spring project:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-framework-bom</artifactId>
<version>${spring.version}</version>
<scope>import</scope>
<type>pom</type>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-releasetrain</artifactId>
<version>${spring-data.version}</version>
<scope>import</scope>
<type>pom</type>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-bom</artifactId>
<version>${spring-security.version}</version>
<scope>import</scope>
<type>pom</type>
</dependency>
</dependencies>
</dependencyManagement>