What are the main keywords used for declaring dependencies in a Gradle file?

In the Gradle file, the following main keywords (configurations) are used to declare dependencies:

• implementation — the main configuration for adding dependencies needed for compiling and running the application, but not exported further.
• api — used in library modules to make dependencies available to consumers of this library.
• compileOnly — dependencies available only at compile time, not included in the final artifact.
• runtimeOnly — dependencies needed only at runtime, not during compilation.
• testImplementation — dependencies used only in tests.

Example:

dependencies {
    implementation 'com.squareup.retrofit2:retrofit:2.9.0'
    testImplementation 'junit:junit:4.13.2'
}

Previously, keywords like compile, provided, and others were used, but they are considered deprecated and replaced with the more precise configurations listed above.