A serial (short for serialization) is like your favorite TV show but as a written story. One installment or chapter is released every week on [insert day and time]. The storyline is broken up into arcs and seasons. Each installment ranges between 1000-2000 words, whereas whole seasons can vary between 10k and 20k.
Shelock Holmes
The Count of Monte Cristo
The Three Musketeers
Dune
Call of the Wild