Hash tag should be given before keywords to highlight the word.This will be useful whenever the users search with that keyword then these posts will be be displayed.

#HashTag can be declared by placing # before any word as you like, for example if you looking for mobile app developers, it world be written in hash tag as follows : #MobileAppDevelopers

This was same for both Twitter and Facebook, you can also use Underscore in between two words.

Use relevant hashtags to make it easy to find your posts on relevant topics.

Use # before the keyword you would like to use on Twitter & Facebook

Hashtags are very trendy. They must be used in trendy keywords so that it can leave a huge impact on the readers of it. Whether you are using Facebook or Twitter, hashtags play a major role in attracting huge members of it. They are pretty helpful for increasing traffic towards a website rapidly.

Use # (hash tag) before keywords to get more searchable on social sites.

You can read more : https://www.postplanner.com/how-to-u...m-google-plus/

A hashtag is simply a keyword phrase, spelled out without spaces, with a pound sign (#) in front of it. For example, #InboundChat and #ChocolateLovers are both hashtags.