Phalaenopsis, the Moth Orchid, is one of the most commonly available and easiest to grow orchid genera. It is an especially good choice for beginners to orchid growing. They have large, showy flowers that come in a wide variety of colors. Most species have several flowers per stem, but some have more, and others have as few as one or two. There are a great many hybrid varieties on the market.
Cattelya – This orchid is probably best known as the corsage flower, since that is where most people first see it. Of the different varieties of orchid, this is the standard that most growers refer to. Cattleya is a native of South America and loves heat and light. Grow them in rooms that feel almost stuffy and place them where they can get as much sunlight as possible without burning them.
The family encompasses about 6–11% of all seed plants.[4] The largest genera are Bulbophyllum (2,000 species), Epidendrum (1,500 species), Dendrobium (1,400 species) and Pleurothallis (1,000 species). It also includes Vanilla–the genus of the vanilla plant, the type genus Orchis, and many commonly cultivated plants such as Phalaenopsis and Cattleya. Moreover, since the introduction of tropical species into cultivation in the 19th century, horticulturists have produced more than 100,000 hybrids and cultivars. 

If your orchid is potted in plastic, place it in an empty bowl, then add water. If you place the plastic pot in an already full bowl of water, the water will push the bark up and out, floating it away from the orchid roots. In this case, add water to just below the lip of the pot and let it sit for 10 to 15 minutes, then drain and return the orchid pot to its place.

Masdevallia is one of my favorite types of orchids! They have triangular flowers (the petals are tiny, so you just see the three sepals.) They need cool temperatures to do well, and like a lot of humidity, but are otherwise quite easy to grow. (But they have a reputation as being hard to grow from people who've ignored their temperature and humidity requirements.)
The seeds are generally almost microscopic and very numerous, in some species over a million per capsule. After ripening, they blow off like dust particles or spores. They lack endosperm and must enter symbiotic relationships with various mycorrhizal basidiomyceteous fungi that provide them the necessary nutrients to germinate, so all orchid species are mycoheterotrophic during germination and reliant upon fungi to complete their lifecycles.
The Gongora orchid genus is a really neat type of orchids, related to Stanhopea. They have nice, strong fragrances, often of cinnamon, allspice, or nutmeg. The flower stems hang over the pot's edge and the flowers point downwards. They can adapt to a wide variety of lighting conditions and a relatively large temperature range, but like a lot of water.
Orchids of all types have also often been sought by collectors of both species and hybrids. Many hundreds of societies and clubs worldwide have been established. These can be small, local clubs, or larger, national organisations such as the American Orchid Society. Both serve to encourage cultivation and collection of orchids, but some go further by concentrating on conservation or research.
The Epidendroideae subfamily is the most widespread subfamily. It represents more than eighty percent of orchid species, and includes over 10,000 types of orchids. Although members of the Epidendroideae subfamily are present in temperate regions, they are most prevalent in the tropics of the Eastern and Western hemispheres. There orchids typically have single anthers with sub-erect structures.
The quality of water used, whether for spraying or watering, is of great importance. Since tap water has often been chemically treated, generally with chlorine, it should be used with caution. The best water for orchids is undoubtedly rainwater. Rainwater, as it passes through the air, dissolves and absorbs many substances such as dust, pollen and other organic matter. This enriched rainwater contributes to the nourishment of the plant.

The Lycaste orchid genus, similarly to its relative Anguloa, likes intermediate-to-bright light, intermediate-to-cool temperatures, and high humidity. The flowers look rather different, though; they are more-or-less triangular in shape because the sepals point outward while the petals point forward. These orchids are very fun to grow, and will thrive if you get their care right.
Epidendrum orchids are among the oldest genera in the orchid taxonomy. Originally, this genus included all epiphytic orchids. As knowledge of the different types of orchids expanded, the classification became much more refined; for example, there are now some terrestrial species in the Epidendrum genus, and a great many other species have been moved to other genera. Still, over 1000 Epidendrum species exist. They are usually easy to grow, and most have tall canelike pseudobulbs that lean all over the place and frequently produce keikis. Fun orchids!
Cycnoches orchids have unisexual flowers, meaning they have separate male and female flowers which look different (usually just one of the two types of orchid flowers each time it blooms). The flowers are usually make a very dramatic display. After flowering, the leaves drop off and it enters a dry rest; don't water until it starts to grow again or it will rot.

Do a finger test. This is the best way to determine whether an orchid needs more water. Stick your pinky finger into the potting mix, taking care not to disturb the orchid's roots. If you don't feel any moisture, or you feel just a little, it's time to water the orchid. If you feel moist potting mix right away, give it more time. When in doubt, you should wait an extra day.
Below are orchid species listed alphabetically, you can go from species to species by scrolling to the top or bottom of any page to find another alphabet bar such as this one below. All names are listed alphabetically including synonyms, so if you see your plant name without a link, there will be a reference there to procede to the name that is on this list with a link to the picture as well as cultural information for your species.
A very showy flower, this type of orchid comes in colors that include white, yellow, brown, purple, red, and a few varieties that are multicolored. They can be a challenge to grow, but they grow well if the temperature is below 80 degrees Fahrenheit because they are used to cool or cold climates. The Odontoglossum orchid has stems that can grow up to four feet high and blossoms that can reach up to six inches in width. Between 20 to 150 blossoms grow on each stem, and their petals are ruffled and very fragrant.
Many neotropical orchids are pollinated by male orchid bees, which visit the flowers to gather volatile chemicals they require to synthesize pheromonal attractants. Males of such species as Euglossa imperialis or Eulaema meriana have been observed to leave their territories periodically to forage for aromatic compounds, such as cineole, to synthesize pheromone for attracting and mating with females.[10][11] Each type of orchid places the pollinia on a different body part of a different species of bee, so as to enforce proper cross-pollination.

The main characteristic of this type of orchid is its very pleasant aroma, which means you will likely smell it even before you see it. The pure white flowers release their scent at night, are frequent bloomers, and can bloom all year long in many places. They are a small but showy type of orchid, and their leaves are long, reed-like in shape, and light green in color. They are also easy to grow and are low-maintenance flowers.

Cymbidium carry tall stems with many flowers that have a more typical orchid shape. They are easily identified by their grassy leaves, and they readily form large clumps. Most common are the cool-flowering types, which need to experience a cooler winter (nights in the 40s for some time in the fall) in order to initiate flowering. Once the flowers open, they can last for up to two months or more, especially in a cool environment. These are very showy and rewarding plants, and a plant in a six-inch pot can carry three stems with 15 or more flowers each, depending on the type.