Hovering the cursor over an icon whilst on the internet will tell you what the icon is. 

Assign or select: graphic of hand or arrows (top, left, right & bottom).

Audio or speaker: graphic of microphone or speaker.

Bluetooth: two Nordic runes overlapping, Nordic H over the Nordic B symbol.

Chat function: graphic of a speech bubble.

Cursor: graphic of an arrow.

Download file: graphic of a cloud with an arrow pointing upwards into it.

Hotspot: two ovals slightly overlapping side by side.

More content: three solid dots in a row.

Notifications: graphic of a bell.

Search: graphic of a magnify glass.

USB connection: a trident which leads from a circle to three recognisable shapes - another (smaller) circle, an arrow-like triangle, and a square.
Wi-Fi: stair-step graphic depicting signal strength.

Desktop computer: a mini desktop screen.

Laptop: a mini laptop.

Mobile phone: a mini smart phone.

Social Media Platforms
Facebook: the letter f, lowercase.

Instagram: graphic of a square camera.

LinkedIn: the letters i & n, lowercase.

Messenger: graphic of a speech bubble with a lightning bolt inside.

Pinterest: a stylised letter P, capitalised.

Reddit: an alien depicted with a smiling face and a broken antenna, bent to the right.

Skype: the letter S capitalised in a cloud bubble.
Snapchat: graphic of a ghost.
TikTok: a single musical note.
Tumblr: the letter t, lowercase.
Twitter: graphic of a bird.
Vimeo: the letter v, lowercase.
WhatsApp: graphic of a speech bubble with a phone hand set inside.
Yelp: the word yelp in lowercase with a flower sitting above the e.
YouTube: a rectangular screen with the triangle play button inside.