The word "lodge" means both a group of Masons meeting in some place and the room or building in which they meet. Masonic buildings are also sometimes called "temples" because much of the symbolism Masonry uses to teach its lessons comes from the building of King Solomon's Temple in the Holy Land. The term "lodge" itself comes from the structures which the stonemasons built against the sides of the cathedrals during construction. In winter, when building had to stop, they lived in these lodges and worked at carving stone.
If you've ever watched C-SPAN's coverage of the House of Commons in London, you'll notice that the layout is about the same. Since Masonry came to America from England, we still use the English floor plan and English titles for the officers. The Worshipful Master of the Lodge sits in the East ("Worshipful" is an English term of respect which means the same thing as "Honorable.") He is called the Master of the lodge for the same reason that the leader of an orchestra is called the "Concert Master." It's simply an older term for "Leader." In other organizations, he would be called "President." The Senior and Junior Wardens are the First and Second Vice-Presidents. The Deacons are messengers and the Stewards have charge of refreshments.
Every lodge has an altar holding a "Volume of the Sacred Law." In the United States and Canada, that is almost always a Bible.
What goes on in a lodge?
This is a good place to repeat what we said earlier about why men become Masons:
The Lodge is the center of those activities.