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Wayback Archive Machine
Before purchasing a domain you like, it is good SEO practice to check the domain's history in case it was spammed or hacked in the past.
We can view the history of a domain in the Wayback Archive Machine . By entering a URL, we will see different dates for which the tool took a snapshot of the website at that time.
If there is no data, the domain you are chad email address going to buy has probably never been used before and is therefore suitable for use.
If there is any registered data from earlier dates, check it out. If the website you see was created a while ago and is decent, you can use the domain. But if you see content that is dubious or dangerous, then it is better to opt for a healthier domain that has not been previously used in bad ways.

Google Trends
Google Trends
Google Trends is a free tool that allows you to see the popularity of a term on Google and the evolution of that popularity over months or years.
This is especially useful if you don't know if a topic is of interest to people. It will also allow you to spot seasonal topics that are only popular at a certain time of year, if something has already gone out of style, or if you're just on the crest of a wave.