What igshid actually is
igshid is Instagram's share identifier. It is attached when a link is copied or shared out of the app, and it identifies the sharing session that produced the URL rather than describing a campaign. You will also run into igsh, a newer form of the same idea, and on Facebook the equivalent is mibextid.
Because it is generated from your action inside the app, it belongs to the share-context family: less sensitive than an advertising click ID, more personal than a campaign label.
Why it matters when you paste links
This is the parameter most likely to end up somewhere public without anyone meaning to. You copy a link from Instagram, paste it into a group chat, a doc or a public post, and the share token rides along. Nothing dramatic follows, but it is unnecessary, and it makes an otherwise tidy URL noticeably uglier.
Is it safe to remove?
Yes. The destination does not need it, and removing it changes nothing about what the visitor sees. The cleaned link from the decoder above is the version worth pasting anywhere that matters.
If you are on the other side of it
Seeing igshid in your own analytics is a useful signal: those visits came from a link copied out of Instagram rather than from a link you tagged yourself, which is word-of-mouth traffic you did not pay for and probably want more of. A tracked Raydar link in your bio records the same visits with location, device and referrer attached, so that traffic stops being anonymous.