Issues of boreir are almost always d'oraita, not d'rabanan, and therefore we are stringent in applying restrictions concerning boreir.
Unlike on Shabbat (when you must remove some good along with the bad so as not to violate the melacha of boreir), on Jewish festivals you may remove the bad from the good if it is easier to take the undesired food from the desired food.

You may select desired food from undesired (or inedible) substances if you follow these two rules:

• Food from other food, or
• Food from other substances.
  Note You may remove dirt from a carrot's surface by scraping the peel with a knife (a tool not specialized for separating food), but not by using a peeler.
  Exception As on Shabbat, an action necessary to eat a food normally (derech achila) does not violate the prohibition of boreir. So you may peel a food that is normally separated from its peel or shell in order to be eaten, as long as you do not use a specialized instrument to do so.

• You may peel an orange by hand, with or without a knife.
• You may remove the shells from peanuts by hand.
• You may remove the shell from a hard-boiled egg by hand.

• Remove fish bones from fish while you are eating the fish or just before eating it.
• Cut open a melon such as a cantaloupe and remove any seeds normally.

Food preparation forbidden on Jewish festivals includes these forbidden melachot:

• Preparing soil for planting (choreish)
• Causing plants to grow (zorei'a)
• Harvesting (kotzeir)
• Gathering (mi'ameir)
• Threshing (dash; such as milking a cow into clean container or squeezing juice for drinking)
• Winnowing (zoreh)
• Selecting (boreir) (for exceptions, see Introduction to Jewish Festivals: Selecting/Boreir)
• Grinding (tochein) (Grinding may be OK with a shinu'i; ask a rabbi for specific cases)
• Sifting (merakeid).

However, you may do all food preparation necessary for baking or cooking food for that day--from kneading dough (kneading, or lash) to cooking and baking (ofeh) from an existing flame.

For women and applying makeup on Jewish Festivals, see Jewish Festivals: Makeup.

Kabbalat Shabbat is mostly omitted when Shabbat falls on:

• Jewish festivals,
• Chol ha'moed, and
• Right after the last day of a Jewish festival. 

On these days, only Mizmor shir... and Adonai malach... are said.
 

Jewish Festivals are listed in the Torah and are of two types: 

1. Three pilgrimage festivals (shalosh regalim):

• Passover,
• Shavuot, and
• Sukkot (including Shimini Atzeret).

These festivals were celebrated in ancient times by "appearing before God"--by bringing offerings to the Tabernacle or Temple.

2. High Holidays: 

• The Jewish New Year (Rosh Hashana—“Yom Teru'a” in the Torah), and the
• Day of Atonement (Yom Kippur).

 
Duration
Jewish holidays that were originally one day are now observed as follows:

• Rosh Hashana--2 days.
• Yom Kippur--1 day.
• Shavuot--1 day in Eretz Yisrael or 2 days elsewhere.
• Passover has festival days at the beginning and end of the holiday and intermediary days of lesser holiness, which are called chol ha'moed. In Eretz Yisrael, Passover lasts for 7 days in total and the first and last days are festival days. Outside of Eretz Yisrael, Passover lasts 8 days and has two festival days at the beginning and two at the end.
• Sukkot has festival days at the beginning and at the end and intermediary days of lesser holiness, which are called chol ha'moed. In Eretz Yisrael, Sukkot lasts for 8 days and the first and last days are festival days (the last day is Shimini Atzeret). Outside of Eretz Yisrael, Sukkot lasts for 9 days and the first two days and last days are festival days (the 8th day is Shimini Atzeret and the 9th day is Simchat Torah).

Character
Each holiday contributes its own character to Jewish life (Passover--the theme of freedom; Yom Kippur brings atonement, etc.). 

Celebrating
How to celebrate these holidays is detailed in our Oral Law and halacha books. Jewish festivals as practiced today are similar in holiness to Shabbat. As with Shabbat, the Jewish festival has candle lighting, kiddush at two meals, and havdala.   We eat our best food and wear our best clothing on Jewish festivals (we eat our next-best food and wear our next-best clothing on Shabbat!).
The main idea behind eating meals on Jewish festivals is joy (simcha), so you should drink wine and eat meat (only if you enjoy wine and meat).  There is no third meal on Jewish festivals since people used to eat two meals each day (adding a third meal on Shabbat was for enjoyment/oneg).
 
Melachot
Any activities or actions permitted on Shabbat are also permitted on the Jewish festivals. Actions that are forbidden on Shabbat are generally also forbidden on Jewish festivals, but there are some leniencies (only if the actions are needed for that festival day).
Examples

• Lighting from an existing flame,
• Cooking and baking for the Jewish festival day, and
• Carrying outside the eruv (hotza'a--transferring objects between domains).

 
Grama
Grama (indirectly causing an action) is permitted on Jewish festivals (but not on Shabbat). For example, you may advance or delay a timer that will make a light go on or off in the future (the timer must already be plugged in and operating from before sunset of the festival day).
Note For an action to be considered indirect based on time, there must be at least 2.5 seconds after the first action is done before the resulting action begins to happen.

Psik Reisha Dla Neicha Lei
Psik reisha dla neicha lei is forbidden on Jewish festivals, just as it is on Shabbat.

D'oraita Restrictions
D'oraita restrictions apply world-wide to:

• First and seventh days of Passover,
• First and eighth days of Sukkot,
• First day of Shavuot,
• Yom Kippur,
• First day of Rosh Hashana.

Note The same restrictions apply to all other Jewish festival days but are rabbinical.
 
Women
In general, women are not required to perform the positive, time-dependent commandments. Women and girls are not required to eat any Jewish festival meals except the Passover seder meal (but they are not allowed to fast on those days).

You should not shave or cut your hair on chol ha'moed.
Reason Chazal made a takana so people would do those types of grooming before each holiday and not wait until chol ha'moed.

For Jewish festivals, cut the upper loaf at night and day.
 

Situation A baby boy is born by caesarean section. The eighth day after the birth is Shabbat or a Jewish festival.

What To Do The brit mila must be delayed to at least the next day following that Shabbat or Jewish festival. (If the mohel or doctor says the baby is not healthy enough for a brit, the brit must be delayed even more.)

Do not check tzitzit on Shabbat or Jewish festivals.
Reason If there is something wrong, you might untangle them and thereby untie a knot, which is prohibited from the Torah.

Note You may not kill bugs on Jewish festivals (or Shabbat). To do something that is certain to kill the bug is forbidden; if might not kill the bug, it is OK.

Pets may be given medicine on Shabbat and Jewish festivals.

Shiv'a ends if a Jewish festival, Rosh Hashana, or Yom Kippur intervenes.
Shloshim ends if a Jewish festival, Rosh Hashana, or Yom Kippur intervenes.
If two of those holidays occur within the first seven days after burial, the first one will break shiv'a and the second one will break shloshim.
Shimini Atseret does not constitute a second day for breaking shiv'a or shloshim (it is considered to be part of Sukkot for this purpose).

For someone who dies during Rosh Hashana, Yom Kippur, or any of the three Jewish festivals, the mourning period does not start until after the holiday has ended.
 

Say she'hecheyanu when lighting candles for:

• Both days of Rosh Hashana,
• Yom Kippur,
• First day (if in Eretz Yisrael) or first two days of Sukkot,
• Shmini Atzeret and Simchat Torah,
• First day (if in Eretz Yisrael) or both days of Shavuot, and
• First day (if in Eretz Yisrael) or first two days of Passover.

On Shabbat and some Jewish festivals, you might want to fulfill some of the quota for making 100 blessings by:

• Eating extra fruit or other foods,
• Hearing and saying amen to the blessings over the:
  • Torah reading,
  • Reader's repetition of the amida for shacharit and musaf, and
  • Haftara by the maftir.