Ok, as a dev who doesn't use github much, I'll give my best guess as to what those icons mean. Respectively:
Home
Alerts
Merging
Documentation
Interactive Heartbeat Sensor, presumably using my webcam, to notify authorities when I'm having a heart attack
Graphs
Branching
Settings
How close was I?
By the way, alt text is absolutely essential for screen readers to function. Don't exclude the blind if they have reason to use your site! Blind people definitely use Github.
Home
Alerts
Merging
Documentation
Interactive Heartbeat Sensor, presumably using my webcam, to notify authorities when I'm having a heart attack
Graphs
Branching
Settings
How close was I?
By the way, alt text is absolutely essential for screen readers to function. Don't exclude the blind if they have reason to use your site! Blind people definitely use Github.