Understand how a niche website works. A niche website focuses on very targeted, specific information. The content must be specific, useful and interesting to your target audience. Successful niche websites get anywhere from 1,000 to 10,000 visitors per month. You build content on a particular keyword, and you make passive income with Google Adsense or through affiliate links.
There are hundreds of online services where you can easily sell your things that are no longer in use. For example, if you’ve an old mobile phone handset lying useless in your drawer, you can sell it on eBay or Cragilist (oh, this Craiglist thing was really useful when I was living abroad!). If you’re in India you can use OLX and Quickr. These are free classified ad websites. Almost all of them have a mobile app as well. All this makes it pretty easy to convert old and useless stuff like CDs, books, clothes, stationary, toys into money.
Proz.com is a site where you can get paid to translate all kinds of documents, including files and even conversations. The site provides you with an opportunity to list your services as a translator. They offer opportunities in Spanish, German, Italian, Chinese, Arabic, Japanese and other languages, and specialize in legal, medical, technical and other fields.
If you have a propensity for writing and you can slay with your prose, consider writing an ebook. While the market has certainly become saturated as of late, books that help teach people about a technical topic still sell extremely well. This is a great source of passive income but does require a large amount of effort at the outset before any money is generated.
Like talking to people and helping walk them through problems? You can bring in extra income as a contract customer support superstar for companies all over the world. Due to the 24/7 nature of online businesses, companies are looking for people in different time zones to help deal with issues that their users are having. Better yet, if you have experience in service or retail you’ll be perfectly suited. Check out indeed or the other remote job boards I listed earlier to find opportunities.
The first known large-scale non-commercial spam message was sent on 18 January 1994 by an Andrews University system administrator, by cross-posting a religious message to all USENET newsgroups. In January 1994 Mark Eberra started the first email marketing company for opt in email list under the domain Insideconnect.com. He also started the Direct Email Marketing Association to help stop unwanted email and prevent spam.  
If you are a budding photographer and would like to be paid for your craft then you should consider setting up your own photography website. This is a great way to not only promote your services as a photographer but also to sell your images. You can charge visitors a fee to download your images. Or, if you’d rather, turn your site into a paid membership site, with free downloads of all images for paying subscribers.
PPC advertising is a method of advertising on search engines like Google and Bing. As mentioned earlier, with PPC ads, you pay each time that ad is clicked on. PPC ads also exist on social media platforms like Instagram and Facebook as well. However, if you're going to engage in PPC advertising, it's important that you determine conversion rates by using tracking pixels.