Bogen, now for some more of your questions.
CW means Morse Code. It stands for continuous wave. For speech (or TV or Fax which some hams also do) one needs to modulate a radio signal, meaning to change it in accordance with the message that is being sent. The radio signal gets louder or stronger with the speech (AM), or changes its freq with the speech (FM). This requires more complicated equipment at the transmitting and receiving end. For morse code, a simple, single, steady radio signal simply needs to be turned on and off to make dots and dashes. This requires much less elaborate equipment and less power. In addition, it can be often be deciphered in the middle of static, as it stands out better.
Probably for this reason, and also for historical reasons (the mesorah of radio which began with Marconi and others in the days of telegraphy before speech was ever transmitted) it was always mandatory for hams to know code. In an emergency, one may be able to use it when nothing else is available. (On a ship, even a simple flashlight will do to send an emergency msg to another ship, if power fails.)
This sort of made ham radio an exclusive club that only those who really wanted to join would put in the time to learn and get tested on code along with the written exam. There used to be 5 levels:
Novice and Technician: 5 WPM (words per minute)
General and Advanced: 13 WPM
Amateur Extra: 20 WPM
The written tests were different for each license as well. The higher the license, the more priviliges. More bands and modes. For instance back then, Novices were only allowed to use CW, and only on a few segments of the ham bands. They could not use voice anywhere in the ham bands, and had to upgrade after 2 years (because Novice license was nonrenewable). They also had an N as the second letter of their call sign to identify them, i.e., WN2XYZ.
You used to get tested by the FCC at their office. They would give the written test in a classroom, and then transmit a 5 minute piece of text and you had to copy 1 minute straight out of that.
Later, the FCC authorized ham clubs to give the tests, and I think the code test became multiple choice at one point, which made it easier.
But the FCC probably bowed to pressure from equipment manufacturers who wanted to get more customers, and they lowered the code requirement to 5 wpm for all classes. Then, about 2 years ago, they did away with the code requirement altogether. This for many is apikursis, a complete break with mesoras avoseinu. It is like interleague play in baseball or the DH rule. But there is an int’l rules body called ITU which is above the FCC, and they gave permission to countries to do away with the requirement, and the FCC decided to do so. Many people still love the code, and use it regularly, altz minhag avoseinu byadeinu. Some use regular telegraph keys, others use electronic keyers which make dots and dashes, and others (the supremely lazy) just type on keyboard and computer generates symbols. (At receiving end most people copy themselves, but computer copying software is available, I believe. This is like reform or reconstructionist branches. Just kidding.)
A net is usually a group of hams who get on a particular freq at a prearranged time for some regular purpose. There are emergency traffic nets, and swap and shops, and code practice groups, and news and info nets, etc.
QRP means lower power. Some hams like to try to get around the world with 5 watts or less, although they may use up to 1000. There is an entire chart of about 40-50 Q signals which are abbreviations that hams use. Aside from abbreviating regular english words which is often done, Q signals abbreviate entire sentences. QRT means stop transmitting, QSO means to make contact with someone. QSL means to confirm receipt (usually with a mailed postcard). QRZ means who is calling me, etc. They were also part of the written tests, I believe.
As far as equipment, there is a wide range in price. If you want simple and used, you can probably get for a few hundred. Antennas also vary widely. There are simple wire omnidirectional setups you can build yourself, or very complicated beam antennas that require a rotor and tower to aim towards a particular direction which concentrate all the power in that one direction, thus giving a strong boost to your signal. There are also amplifiers which take the normal 100-150 watts a transceiver will put out, and boost it to 1000 watts. (These monsters use a lot of electricity, needless to say, and probably big vacuum tubes, as in old radios.) Many hams have an entire room filled with equipment, not just a transceiver. (Hams love gadgets.) You can save money if you are good with your hands and like building things, but you must be careful, as this kind of voltage is dangerous.
Field day is only once a year, so most people do most of their operating from home. There are also other contests which you can do from home, as well, during the year. The halachos of field day are that no power lines can be used, only from generators.
In general contesting is different than regular contacts, because you just exchange a location and some other short info according to the rules of that contest, and then go on to someone else to get more points. Normally, you might speak to someone for a long time without time pressure.
There are clubs that have regular meetings about once a month, in addition to various hamfests and outings and field day where people get together. But most of the time you operate from your home or car.
It is worthwhile to get some intro books on ham radio. Many libraries may have some, and you can look on ARRL site for much info and the names of books. I think they have some videos you can watch about the hobby. The best thing is to find a rebbe (called an Elmer for some reason) who has been a ham for a while and will guide a talmid through the process. If you find a club near you (from the ARRL site or from a list published in their magazine, QST), they will be happy to find you someone local. There may be regular classes offered by a club near you, although you are free to study on your own. You can probably call the ARRL in Newington, CT and they would look up which clubs are near your location, and may even be able to refer you to an individual whom you could visit and see his station. Most are extremely friendly, and love showing their station to people. For many people this hobby is their entire life. They think about nothing else 24/7. I was like this when I was a kid.