How many pages should an ebook be?

This question is debatable, but the most important aspect is the quality of the content which is in the ebook, rather than the quantity/amount of the pages the ebook contains.

A 30 page ebook with valuable content would be far more valuable than a 200 page ebook with weak poor content.

I tend to think anything between 10- 200 pages for an ebook is substantial.

Remember is quality not quantity that counts.
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Podcastes are a great way to provide a variety of content to your visitors compared to an ebook or article.

Podcastes and videos are sometimes underused by marketers yet they can be very powerful ways to get your message across.

When you create them and get comments from your visitors then that gives a great feeling, and the traffic that your podcasts can generate is even better.

Here is a some creative wording I have made:
[P]roduce podcasts to...

How do Backlinks work?

Backlinks work by giving some links to your website, by linking your home page from another website related to yours. This points the other website to yours, which is one factor that can increase your websites rankings.

Your site: Baseball tips
Another related site: Baseball items for sale Blog

You get a link pointing from the Baseball blogs site to your site, (by contacting the site owner).

The link can point to your...