Raspberry

raspi-config

Most settings can be modified via raspi-config

raspi-config

Enable/disable overlay to be able to make permanent changes.

raspi-config  --disable-overlay
raspi-config  --enable-overlay

which version of raspberry do you have?

cat /proc/cpuinfo

which version of raspian

cat /etc/os-release

Black lines

/boot/config.txt

overscan_left=-40
overscan_right=-40
overscan_top=-40
overscan_bottom=-40

disable_overscan=1

Installed packages

sudo apt -y install autofs screen vim htop ntp

omxplayer

ar vx /path/to/your/file.deb data.tar.gz 
tar xzf data.tar.gz -C / 
rm data.tar.gz

rename

/etc/hostname
/etc/hosts

temperatur

vcgencmd measure_temp

list content of package

dpkg-query -L <package_name>

which package contain file

dpkg --search /etc/bash_completion

is clock in sync

timedatectl

enable ntp

timedatectl set-ntp true

connect to wifi

sudo wpa_cli -i wlan0 select_network 1

list save wifi networks

sudo wpa_cli -i wlan0 list_networks
network id / ssid / bssid / flags
0       [-_-] halfface 2.4      any     [DISABLED]
1       pepsi   any     [CURRENT]

restart wifi

sudo wpa_cli -i wlan0 reconfigure

log2ram

https://github.com/azlux/log2ram