The console app in macOS is a system-wide display program for troubleshooting messages and log files. You can use it to track errors in applications or just get an idea of what is happening in your system.
Most of this app is not intended for the average user to see, as it is made for developers who have a better understanding of MacOS operating systems. Warnings and errors are common in normal use of your computer, so don't worry if you see a lot of them here.
Reading the console
You can start the Console app from Spotlight by pressing Command + Space and looking for it or from the Tools folder in your application directory. (Open Finder and select "Program" to find it.)
The first thing you see is the console itself. It logs every message sent out by processes and services running on your system. It is updated very quickly, so you have to use some sorting if you want to make any sense about it.
Up in the toolbar there is a button called "Now" will automatically scroll through the window when new messages come in. It can be useful if you are trying to troubleshoot in real time.
You can also choose to show only errors and Errors that will filter everything but a red or yellow dot next to it and just show important things you might want to see.
There is also a search field here, which has the extra functionality to be able to search for different parameters. Just type something in, press Enter and then change the parameter from the "Any" drop-down menu:
You can use this to restrict the console to display only messages that are relevant to your problem.
Another view is the "Activities" panel, which sorts console messages according to the activity they are associated with:
These are ordered hierarchically, so you must click on the white "+" button next to where and one to expand it.
The system logs act as more detailed and more permanent console messages. You can find them in the "Reports" section of the sidebar.
The lists are divided into different categories, and you will find most user-level applications that have their logs in "~ / Library / Logs", shared by the application. Lower level processes can have their in "/ Library / Logs" or "/ var / log." These are all on the disk so you can navigate to these folders to copy the file yourself if you need to send it to someone else
There are also the categories "System Reports" and "User Reports", which group logs for system processes and user programs.