Do all muscles attach via tendons? What exactly is an "indirect attachment"?

The way a muscle attaches to bone or other tissues is either through a direct attachment or an indirect
attachment. A direct attachment (called a fleshy attachment) is where the perimysium and epimysium
of the muscle unite and fuse with the periosteum of a bone, perichondrium of a cartilage, a joint capsule,
or the connective tissue underlying the skin (some muscles of facial expression being good examples of
the latter). An indirect attachment is where the connective tissue components of a muscle fuse together
into bundles of collagen fibres to form an intervening tendon.