MacPPP is an implementation for Macintosh computers of PPP (Point to Point Protocol) which allows you to connect your Mac to the Internet using dialup modem lines. For modern Apple computers, MacPPP has been largely replaced by other software, but it is still the connection of choice for 68K Macs. There are a number of versions of MacPPP freely available, but the one which is recommended by the "experts" for System 7 is version 2.1.2SD, and this is what I used for my connection.

MacPPP consists of a control panel named Config PPP and a system extension named PPP. If they are dragged over the System Folder in System 7, then your Mac will put them in the right folders for you.

With regard to configuring MacPPP, here are some pages giving details of how to fill in the Config PPP settings; here's the first page, and here's the second one.

MacTCP is a commercial software product produced by Apple. For the user, it is a hybrid of a Control Panel and a System Extension; it is configured just as the Monitors or Sound panels are. For applications, it is a set of procedures which allows them to communicate with other hosts on the network using the TCP/IP protocol. It is designed to be transparent in the sense that once it is properly configured, any correctly written application can make use of it without user intervention.

The version of MacTCP to use on the Classic Mac is 2.0.6.

With regard to configuring MacTCP,Here are some pages giving details of how to fill in the MacTCP settings;here's the first page, and here's the second one.