Five tragedies occured on the Tamuz 17.

1. The first set of Tablets (10 Commandments) were broken.
2. The two daily sacrifices were suspended.
3. The enemy penetrated the walls of Jerusalem.
4. The Wicked Apostumos burned a Torah scroll.
5. An idol was erected in the Bais Hamikdosh (Temple).

The Three Weeks begin on the 17th of Tamuz  and end on Tisha B’Av.

The following items should be curtailed or eliminated:

• Engagements
• Weddings
• Playing musical instruments
• Purchasing a new garment that one make a Brocho of Shechayonu over
  1. The Mishna Brurah (551:45) says that you may buy shoes and socks in the 3 weeks because we do not say Shechayonu on them.
  2. It follows therefore that if you do not say Shechayonu on a new suit you may buy it (and wear it) in the 3 weeks (till Rosh Chodesh Av).
  3. However, it is preferable not to buy something that will give you Simcha (Oruch H’Shulchan).
• Eating a new fruit
• Haircuts

  1. However, women are allowed to cut their hair for modesty reasons.

  2. Additionally, women are permitted to tweeze or cut their eyebrows and eyelashes and shave or wax to remove any body hair.

• Listening to music

  1. You are permitted to hear/listen if it is not for pleasure. Therefore in the following situations, you may listen to music:

  2. Someone who is in hospital and they need music to relax or to remain calm.

  3. If you are traveling and you need the music to stay awake.

  4. You need background music to help you concentrate while you work.

  5. You need music to exercise.

      

      

•   Even in the above situations, it is preferable not to listen (unless it is necessary).

• During the Three Weeks you are permitted to conduct regular business dealings.
• You may begin construction or renovations of your home, during the Three Weeks until Rosh Chodesh Av.
• After Rosh Chodesh if the work is being done by a Jewish contractor you are not permitted to continue during the Nine days (A shailoh should be asked).
• However if the contractor is a non-Jew the Mishna Brurah 551:2 says if it is possible (with minimal loss) you should try to push the contractor off until after Tisha B’Av V’Tovo Alov Brocho (you will be blessed). 
• It is permitted to hire a contractor during the three weeks to do any necessary repairs in your home.

• The fast begins at Dawn (Alos) and ends at nightfall (like Shabbos).
• An elderly or unwell person is not permitted to fast, if fasting is detrimental to their health (even slightly)·
• Women who are pregnant or nursing should not fast if it is difficult for them.
• If you are not fasting [pregnant, nursing, elderly or sick] you may eat, first thing in the morning and you do not need to fast until Chazos.
• It is preferable not to eat in a public place (restaurant etc..).
• You may have a shower/bath on the fast. (The Mishna Berurah brings that some are Machmir not to have a hot shower).
• You may brush your teeth without water or use mouthwash if you are very uncomfortable.
• You may eat in the morning before Alos H’shachar if you had in mind to do so before you went to sleep (you may have a drink even if you did not have in mind).

• You are allowed to have a Sheital cut and set in the Three Weeks (till Rosh Chodesh Av).
• You may dye a Sheital. 
  
• You are allowed to cut your nails in the Three Weeks (The week of Tisha B’av [The week Tisha B’av falls in], is a Machlokus if you may cut your nails).