In the USA, 17 U.S.C. § 107 states:
Notwithstanding the provisions of sections 17 U.S.C. § 106 and 17 U.S.C. § 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include:
The fact that a work is unpublished shall not itself bar a finding of fair use if such finding is made upon consideration of all the above factors.
The first step would be to determine what copyright exists and whether it covers the portion of the work you intend to use. If not, then the whole question is moot.
Once you have established that what you want to use is indeed covered by copyright, you need to examine the 4 issues raised in the law cited above. You need to determine the intent of the use of the portion of the work. Is it for
Note that you still have to be very careful when it comes to using copyrighted material for teaching. A teacher can't just pirate copies of a text or a piece of software instead of purchasing them for use by the class. On the other hand, a teacher can fire up a copy of Word to teach students how to use it or to illustrate how point-and-click works without having to pay Microsoft for the use of their product. If they turn around and use that same copy of Word to write letters to the parents of the students, then they had better have a license for the software!
You need to establish how much of the work you are using. Citing a paragraph from a book is usually OK. Quoting a whole chapter is usually not OK. Demonstrating one feature of a piece of software to illustrate a point in a presentation is usually OK. Using the software to run your presentation for a bunch of paid lectures probably would not be.
You need to establish whether you are using the work to make money without the permission of the copyright holder.
If your use of the product is preventing others from buying it because you are making it free for them to use, it's not going to be "fair use".
Although all this discussion is specific to US law, the concepts are at least close to the way the laws are applied in most other countries. Note that in a lot of countries they either have no "fair use" statutes on the books or turn a blind eye to people appropriating copyrighted products without paying for them. Even if you are not punished for this, it's still wrong.
The overarching question should be - am I cheating the copyright holder out of money they should be getting for this product?
You should perform maintenance on your water heater, including cleaning it, at least once a year to ensure it functions efficiently.
Management should ensure this.
In Islam, it is important to perform a ritual cleansing called "istinja" after menstruation. This involves washing the private parts with water and ensuring that they are clean. It is also recommended to perform a ritual ablution called "wudu" before prayer to ensure cleanliness.
To ensure food safety and prevent bacteria growth, it is recommended to perform a thorough cleaning inside your refrigerator at least once every month.
It is recommended to perform a deep clean of your fridge every 3-4 months to maintain cleanliness and hygiene.
Job rotation
To perform ghusl for janaba in Islam, one must first make the intention to purify oneself. Then, wash the private parts, perform wudu (ablution), and pour water over the entire body three times. It is important to ensure that water reaches every part of the body, including the hair and skin. After completing the ghusl, one should pray two rakats of voluntary prayer.
To ensure the health of your fish, perform a full water change in your fish tank every 2-4 weeks. This helps maintain water quality and keeps your fish healthy.
It is recommended to perform maintenance on your flushing hot water heater once a year to ensure it continues to function efficiently and prevent any potential issues.
To ensure optimal performance and longevity of your moka pot, it is recommended to perform a deep clean every 1-2 months. This will help remove built-up residue and maintain the quality of your coffee maker.
To ensure the longevity and optimal performance of your guitar, it is recommended to clean the fretboard and perform maintenance tasks every 3 to 6 months, or more frequently if you play regularly or notice buildup of dirt and grime.
No, you should not attempt to remove an Essure coil yourself. The procedure requires medical expertise and proper instruments to ensure safety and prevent complications. If you wish to have the coils removed, it's important to consult a healthcare professional who can perform the procedure safely.