Characteristics

Small (total size: 44MB for 2,300 ports)
Don't have to keep original source (distfiles) around
Checksum protection of distfiles
Security
Easy to upgrade (no source!)
Categorized for searching
/usr/ports/<category>/<port>
Real categories and virtual categories (symlinks)
Allows user to delete the software completely
Don't touch site configuration files
Checksum verification for changed files
Dependency
Compile and run time
Runtime dependencies propagated to packages too

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