the portable center of worship used by Israel during the 40 years in the desert (and in the land until the temple was built).
Detailed instructions for building the tabernacle (Hebrew: mishkan), and a detailed record of the building, are given in the later chapters of the book of exodus. The book of leviticus then describes in detail the rituals to be performed in it and the annointing of the priests who will perform these rituals. (There is further information in the remaining books of the torah.)
The tabernacle consisted of an outer wall, a courtyard where offerings were made, and an inner sanctum, the holy of holies, housing the ark containing the tablets of the law. There were two altars, a larger one for animals and a smaller one for incense, along with a menorah (candalabra), a table with "show-bread", and curtains for separation. This was all set up when the Israelites stopped at a place in the desert, and dismantled and carried when they moved. Sub-groups of the tribe of Levi were charged with the care of different pieces.