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How does a monophyletic group differ from a paraphyletic group?

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A diagram showing the tentative evolutionary relationships among hominid species over the past four million years, with skull images and labeled species names connected by solid and dotted lines to indicate proposed evolutionary pathways. — phylogeny Tentative phylogenetic scheme for the evolution of the human lineage. Solid bars indicate the time ranges during which species are thought to have existed, based on fossil evidence. Dotted lines signify evolutionary relationships between hominin species that have been proposed on the basis of the fossil evidence.

In phylogeny, the distinction between monophyletic and paraphyletic groups is based on how much of an evolutionary lineage is included in the classification.1

Monophyletic group: Also known as a clade, this group consists of a common ancestor and all of its descendants. Visually, you can isolate a monophyletic group from a phylogenetic tree with a single cut.12
Paraphyletic group: This group includes a common ancestor but only some of its descendants, intentionally excluding others. Identifying this group on a tree requires multiple cuts, as it does not capture the complete lineage stemming from the ancestor.1

These classifications are essential for cladistics, a system of taxonomy that organizes organisms based on their inferred evolutionary relationships and shared ancestry.13