One of the most commonly used command when troubleshooting a switch or router is the "Show Run" command. It gives you an insight into the currently running configuration.
Sometimes, this command yields so much output one would be overwhelm with the amount of text on the screen and have to keep pressing the space key to scroll down to see more information.
Well, if you know what you are looking for then you could add a command prefix " begin keyword" and it'll start showing the configuration from that where the keyword occurs.
SwitchA# Show runn | begin spanning-tree
In the example above, the switch will show the current configuration from the line where it finds the first occurrence of the word "spanning-tree".
Using this command can really save you all the trouble of spacing through all the text only to find that you go too fast and miss the relevant information and have to scroll back to look for it.