Cardiac muscle tissue can only be found in your heart, where it performs coordinated contractions that enable your heart to pump blood throughout your circulatory system. Cardiac muscle tissue uses involuntary movements to keep your heart pumping. This is one feature that distinguishes it from controllable skeletal muscle tissue. Pacemaker cells are specialized cells that help it do this. These are in charge of your heart’s contractions. Pacemaker cells receive signals from your nervous system that tell them whether to speed up or slow down your heart rate. The pacemaker cells in your heart are linked to other cardiac muscle cells, allowing them to send and receive signals. This causes a wave of cardiac muscle contractions, which produces your heartbeat.
Source: https://www.healthline.com/health/cardiac-muscle-tissue#function

Thousands of muscle fibers are wrapped together by connective tissue sheaths in each skeletal muscle. Fasciculi are the individual bundles of muscle fibers that make up a skeletal muscle. Epimysium is the outermost connective tissue sheath that surrounds the entire muscle. The connective tissue sheath covering each fasciculus is known as perimysium, and the innermost sheath surrounding individual muscle fiber is known as endomysium. Each muscle fiber is made up of several myofibrils, each of which contains multiple myofilaments. Sarcomeres, the fundamental contractile unit of skeletal muscle, are formed when myofibrils are bundled together in a unique striated pattern. The skeletal muscle’s primary functions are controlled by the intrinsic excitation-contraction coupling process.
Source: Anatomy, skeletal muscle – StatPearls – NCBI bookshelf. (2021, September 5). National Center for Biotechnology Information. https://www.ncbi.nlm.nih.gov/books/NBK537236/#:~:text=Skeletal%20muscle%20is%20one%20of,muscle%20are%20known%20as%20fasciculi

Seladi-Schulman, J. (n.d.). Cardiac muscle tissue: Function, structure, conditions, and pictures.

Smooth muscle, also called involuntary muscle, is the muscle that shows no cross stripes under microscopic magnification. It is made up of narrow spindle-shaped cells with a single nucleus in the center. Smooth muscle tissue, unlike striated muscle, contracts slowly and automatically. It constitutes much of the musculature of internal organs and the digestive system.
Source: Smooth muscle. (n.d.). Encyclopedia Britannica. https://www.britannica.com/science/smooth-muscle