These versions of Worldcraft serve more as historical curiosities than usable level editors. While still perfectly functional, these old versions simply aren't as efficient as newer alternatives that have cropped up since their release. J.A.C.K. is a much newer, faster, 64-bit editor that functions near-identically to Worldcraft/Hammer.
Worldcraft is one of the first notable level editors for Quake-based games. You might better know it as the Valve Hammer Editor, which is included with both the Half-Life SDK and Source SDK. After Worldcraft 1.2 was released, the then-nascent Valve Software bought the rights to the editor and included it as the official pack-in level editor to Half-Life. Worldcraft was later renamed Hammer and now comes standard with any Source games you might own.
The concepts and workflow established in Worldcraft are still used in modern versions of Hammer and editors similar to it (known as Worldcraft-like editors, such as J.A.C.K. or Sledge). The use of multiple 2D viewports for editing supplemented by a 3D viewport for previewing the level, separate tools for selecting, creating brushes, placing entities, and applying textures, a pop-up dialog for sorting and selecting textures, and more advanced tools such as the Cordon tool and the Expert Compile options dialog were all introduced in early versions of Worldcraft.
This page will serve as the hub for any versions of Worldcraft/Hammer we happen to come across. All of these versions are meant to work with Quake, Quake II, and GoldSrc games, and versions supported are listed with each individual version. These downloads don't require installation, though the 1.x versions expect to be run from C:\Program Files\Worldcraft or they'll otherwise work improperly. Hammer 4.0 and later are required to map for Source games and are available with the games themselves, in their bin directory.
Navigating the viewports
The biggest changes between early (pre-2.1) and more modern versions of Worldcraft that are likely to trip up newcomers are the ways you maneuver around each viewport. Early Worldcraft isn't without mouselook or other such functions, though the way you utilize them is different from later versions.
You can pan around any of the 2D viewports by holding the spacebar and dragging with the mouse. This also orbits the camera in the 3D viewport. (In 1.1, you'll need to select the Camera Tool before you can orbit in the 3D viewport.)
The D and C keys zoom in and out of the 2D viewports, respectively.
D and C are also used to move the camera forward and backwards in the 3D viewport. The S and F keys will roll the camera left and right.
You can also draw out cameras using the Camera Tool. You can have as many as you'd like, cycle between them with Page Up and Page Down, delete them with the Delete key, and they'll be saved in the map's RMF file. If you have multiple, the above controls will manipulate the currently active camera.