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).

Muktza (“set aside” in one's mind) is an item that normally has no permissible use (or no use) on Shabbat. Muktza items may not usually be moved by hand on Shabbat—even if your hand is gloved—except for certain Shabbat needs, such as you need the space or the item. However, it is ALWAYS OK to move muktza items with any other part of your body.
  Chazal instituted muktza rules to make Shabbat special by requiring that actions be done differently on Shabbat than on weekdays. The basis for the idea of muktza was when Moses/Moshe instructed the Children of Israel in the wilderness to prepare the mun for Shabbat in order to eat it on Shabbat. Chazal extended the idea to prohibit moving by hand on Shabbat anything that was not prepared in one's mind before sunset on Friday.
The several categories of muktza vary according to their purpose and their permissibility to be moved. Purpose Item whose normal purpose is forbidden to be done on Shabbat.
Permissibility To Be Moved You may move this item by hand, without using a shinu'i:

• If you need the space where it is resting, or
• For a permissible use.

• Using a hammer to open a coconut.
• Using pliers to crack open nuts.
• Using a portable radiator to prop open a window.

No prior preparation or thought before Shabbat is required.
Note You may not move it just to protect the item.

Muktza Machmat Gufo: No Use
Purpose An item that has no use. This item is not normally ever designated for use; for example, a rock or stone. However, an item in this “no use” category is rendered non-muktza and usable on Shabbat as long as you had intended--before Shabbat or the festival began--to use it for a permitted purpose. As long as you intended that, you do not even need to use a shinu'i. If you did not intend, before sunset on Friday, to use this normally unusable item, then you may only move it using a shinu'i.
Permissibility To Be Moved Unless you prepared before Shabbat to use it for some permitted purpose on Shabbat, you may not move it by hand even for a permitted use and not even in order to use the space where it is resting.
Note You might need to use the item regularly for the non-standard purpose because for just a one-time use, it might not be permitted. Consult a rabbi.
Exception Garbage has no use. You may move garbage within your house (example: push the garbage across the room with your foot), but if you want to dump your garbage outside and you have a private domain or an eruv, you may pick it up and carry it outside.

Muktza Machmat Chisaron Kis
Purpose A valuable item that you are concerned may be damaged.
Examples Passport, porcelain china, or other expensive and fragile or difficult-to-replace objects.
Such an item may not be moved except for its designated purpose and you may not move it once you have finished using it. But once you are already holding it, you may take it to a place where you want to leave it and you do not need to drop it where it is when you finish with it.  

Basis L'Davar Ha'Asur

Purpose Muktza item resting on a normally permitted item makes the lower item muktza too.
Example A candlestick will render the table on which it stands muktza (unless there are one or more other items that are more valuable than the muktza item, in which case the table does not become muktza).
Situation There are multiple objects; some are permitted and some are not—for example, in a drawer.
What To Do If the permissible objects are more valuable than the non-permitted objects, you may open the drawer.

Non-Muktza on Top of Muktza
If you want a non-muktza item that was left on top of a muktza item from before Shabbat started, you may use it without restriction.

 

Situation

You discover you have coins in non-patch pockets of your pants that you will wear on Shabbat.

What To Do

You may empty coins out of non-patch pockets if you need to use the pants, but not by taking the coins out: you must dump them out of the pockets.
Note If you have coins in a patch pocket, the whole garment is muktza, unless you forgot that the coins were there or if you intended to remove the coins before Shabbat began but forgot to remove them (in which case you may shake the coins out of the pocket and the garment is not muktza).

Non-Patch Pockets

Situations

Pants with muktza items in the pockets are on your bed and you want to sleep on Shabbat afternoon.

What To Do

You may move the pants off your bed using any body part including your hands; no shinu'i needed.

Item that Becomes Muktza
If you are holding a permissible item and it becomes muktza, you may put it in safe place; you do not need to immediately drop it or put it down where you are.
Example You are holding a pot from which you dispense all of the food. The empty pot is now muktza, but you may take it to the kitchen to put it down.

For More Information about Muktza

To see the TorahTots article on muktza, click here.

You may say ma'ariv on Friday afternoon (erev Shabbat) as early as plag ha'mincha (1 1/4 halachic hours before sunset), as long as you say mincha before saying ma'ariv. So, if it is now plag ha'mincha, you may say mincha and then follow it as soon as you wish with ma'ariv.

For greetings for the New Year, say:

• “Ketiva V'Chatima Tova”

              From: Rosh Chodesh Elul
              Until:  Eve of (erev) Rosh Hashana (when the holiday begins).

• “L'Shana Tova Tikateiv V'Tichateim”

            From:  First night of Rosh Hashana (when the holiday begins)
            Until:   Musaf of the first day of Rosh Hashana.

• “Gmar Chatima Tova”

               From:  Musaf Rosh Hashana
               Until:   End of Yom Kippur.

• “Gmar Tov”

               From: Yom Kippur
               Until:  Musaf Hoshana Rabba.
 

Some communities have the custom of an onen's saying kaddish.
NOTE When a person's parent dies on or just before (erev) Shabbat or a Jewish festival, a daughter of any age should not be told until after Shabbat or the festival is over. A son should only be told if he is 6 years old and above and the custom in that community is to say kaddish as an onen.

Restrictions during the Nine Days before Tish'a b'Av are the same as for Three Weeks, plus:

• You may not eat meat or drink wine.
  Exceptions

  1. You may drink wine on Shabbat (but not on Rosh Chodesh Av or erev Shabbat.)
  2. You may drink wine for havdala (but ideally give the wine or grape juice to a child between ages 6 and 10).  
  3. You may eat meat or drink wine at a brit, siyum, or pidyon ha'ben.
• You may not wear freshly laundered clothes, or wear or buy new clothes.

• You may not wash yourself for pleasure.
  Note Showering or bathing to clean one's soiled body is permitted (except on Tish'a b'Av).  So you may bathe or shower during the Nine Days if you are dirty, sweaty, or smelly.
• You may not do any activities that involve luxury.
• You may not say she'hecheyanu except on Shabbat.
  Note Therefore you should not buy new fruits or new items that you will enjoy during the Nine Days.  But if you DO eat a new fruit or buy something new, you must say she'hecheyanu anyway.

Food Nullification in Utensils: Torah-Law and Rabbinic Decree
By Torah law (d'oraita), any clean utensil, countertop, etc., automatically reverts to neutral/pareve and kosher after not being heated to more than 120° F (49° C) for 24 hours.
But by rabbinic decree, utensils do not automatically become neutral/pareve even after 24 hours and must be kashered by heat (libun—direct heat; hag'ala—boiling in a pot; or eruy rotchim—pouring boiling water over item) or, if some types of glass, by soaking in water (meluy v'eruy ).
 
Changing Gender of Utensil
You may kasher a pot or cooking/eating utensil from:

• Non-kosher to kosher, or
• Year-round use (chametz) to kosher for Passover.

 
You may not intentionally kasher a utensil in order to change it from dairy to meat or meat to dairy; you must first kasher it from accidentally (or intentionally) non-kosher to kosher/pareve, or from non-Passover to Passover/pareve. You may then use it for either dairy or meat.

Once you have used it for that gender, the item retains that gender (unless you re-kasher it for Passover or you make it non-kosher first, then kasher it to neutral/pareve).
But if you accidentally heat meat with a dairy utensil or vice versa, you may kasher it back to its original gender by any one of the kashering methods, depending on how it became non-kosher.
 
Items/Materials that Can Be Kashered
The following materials can be kashered:

• Glass, including Corelle, if not used directly on the stove or oven. Glass does not change gender or other kosher status unless heated on a flame or in the oven. Unless it is heated in this way, glass does not ever need to be kashered (except for Passover) (see Meluy v'Eruy, below).Glass, including Corelle, if not used directly on the stove or oven. Glass does not change gender or other kosher status unless heated on a flame or in the oven. Unless it is heated in this way, glass does not ever need to be kashered (except for Passover) (see Meluy v'Eruy, below).Glass, including Corelle, if not used directly on the stove or oven. Glass does not change gender or other kosher status unless heated on a flame or in the oven. Unless it is heated in this way, glass does not ever need to be kashered (except for Passover) (see Meluy v'Eruy, below).

• Granite (not granite composite)
• Marble
• Wood, if smooth (see notes on Eruy Rotchim, below)
• Metal, including stainless steel, cast iron, and aluminum.

Note While metal can be kashered if thoroughly cleaned, welded handles and other difficult-to-clean parts may render a metal utensil not kasherable. You might be able to use libun kal on the problematic area and still use hag'ala for the remainder of the utensil.
 
Items/Materials that Cannot Be Kashered

• China
• Corian
• Corningware
• Crockpot
• Formica
• Glass that has been used directly (kli rishon) on a stove or in an oven; however it can be kashered in a kiln
• Granite (composite)
• Knives with Plastic Handles (knives with wooden handles may be kashered if there are no cracks in the wood and if the rivets do not have spaces that catch food and prevent you from cleaning it completely)
• Mixer-there might be exceptions. Consult a rabbi.
• Plastic
• Porcelain (Enamel)
• Pyrex (if used directly on stove or in oven--kli rishon)
• Rubber (synthetic)
• Silestone
• Silverstone
• Stoneware
• Teflon
• Toaster/Toaster Oven
• Waffle Iron.

 
Pot Lid Handle
Kashering
The handle on a pot lid does not need to be kashered for normal use during the year. 
Reason It does not normally get hot.
Cleaning
However, the pot lid handle must be removed and the lid cleaned where the handle attaches, if possible.
Note If the gap between the handle and lid cannot be completely cleaned, you may not use that lid for Passover and you normally may not kasher it if it becomes non-kosher. If the lid handle cannot be removed, consult a rabbi.

Pot or Pan Handle
A plastic handle that gets hot, especially if it is over a flame on a burner, may not be kashered. If the handle becomes non-kosher, it must be replaced. If a plastic handle connects directly to the metal of the utensil, consult a rabbi about what to do.
 
Food Nullification: Heat-Kashering
Three Methods of Heat-Kashering
Heat-Kashering is of three types:  Libun, Hag'ala, and Eruy Rotchim.

1. Libun (Direct Heat)
   How It Works  Burns up any residual food taste

       

• Direct a flame, such as a blowtorch, onto the inside of a pot. Pot is hot enough when a piece of paper that touches the outside of the utensil burns (it does not need to burst into flame, just to smolder), or
• Put the pot into the oven at 500 ° F for 40 minutes. (First, remove any non-metal handles; they will need to be kashered separately or not used.)

   

2. Hag'ala (Boiling)
    

• Boil Method Boiling water within the pot to be kashered, and making the boiling water overflow, or
• Dip Method Dipping a smaller pot or utensil to be kashered into a larger pot of boiling water.

       

• If the pot in which you are kashering the items had been heated to 120° F (49° C), with food of that gender in the pot, or more within the previous 24 hours, the items you are kashering will assume the gender of the pot.
• If the pot in which you are kashering the items had NOT been heated to 120° F or more for at least 24 hours, any items that are kashered in it will become kosher and pareve.

     
 

3. Eruy Rotchim (Hot-Water Pour)

         

 
Food Nullification: Meluy V'Eruy
Meluy V'Eruy To Kasher Glass
Halachically, “glass” includes Arcoroc, Corelle, crystal, Duralex, and Pyrex.
NOTE In pre-war Europe, where glass was expensive and hard to obtain, it was customary to kasher drinking glasses, especially for Passover, by soaking the glasses for three 24-hour periods (meluy v'eruy), as follows:
Step 1: Submerge glasses in cold water for 24 hours.
Step 2: Empty water, refill, and submerge glasses again.
Step 3: Repeat Step 2.
NOTE If any of these materials were heated directly on a flame or other heat source, they cannot be kashered by meluy v'eruy!