Hashtags became very popular on Twitter and are also an important part on Instagram. Hashtags consist of a hashtag (#) and a (key) word (e.g. #instazeal) and are great for getting your content found organically by others on the platform.
Instagram uses the hashtags you use with your image or video to categorize your post and display it in the relevant feed for the hashtag. This allows any of the 700+ million users searching for #newyork, #london, #tokyo to find your image under the hashtags you used.
It is important to note that hashtags cannot consist of periods (.), symbols (!&é), or spaces. However, hashtags can consist of emojis, underscores, lowercase and uppercase letters, and numbers.