what are different types of it?
Fresco-secco, "mezzo-fresco"
Fresco
A secco or fresco-secco painting is done on dry plaster 
lord make me the channel of thy peace UNANSWERABLE what was the prayer of saint francis about? It is a widely known Christian prayer for peace. who is the saint mentioned? Francis of Assisi was an Italian Catholic friar, deacon, mystic, and preacher. what does the last mentioned term mean? A preacher is a person who delivers sermons or homilies on religious topics to an assembly of people. was he a traveler too? UNANSWERABLE has he written any book? Saint Francis is considered the first Italian poet by literary critics. He believed commoners should be able to pray to God in their own language, and he wrote often in the dialect of Umbria instead of Latin. was he interested in art? There are large early fresco cycles in the Basilica of San Francesco d'Assisi what is this art form about? It  is a technique of mural painting executed upon freshly laid ("wet") lime plaster. how did it get the name? The word "fresco" () is derived from the Italian adjective "fresco" meaning "fresh", and may thus be contrasted with fresco-secco or secco mural painting techniques, which are applied to dried plaster, to supplement painting in fresco.
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Fresco [SEP] Other types of wall painting
A secco or fresco-secco painting is done on dry plaster ("secco" meaning "dry" in Italian). The pigments thus require a binding medium, such as egg (tempera), glue or oil to attach the pigment to the wall. It is important to distinguish between "a secco" work done on top of "buon fresco", which according to most authorities was in fact standard from the Middle Ages onwards, and work done entirely "a secco" on a blank wall. Generally, "buon fresco" works are more durable than any "a secco" work added on top of them, because "a secco" work lasts better with a roughened plaster surface, whilst true fresco should have a smooth one.