14/10/2020
EDIT MODE
An object in Blender in the edit mode is defined by its vertices, edges and faces. If we consider a square plane, it has four vertices at the four corners,four lines(called as edges in Blender) connecting these four vertices and a surface (called face in Blender) which stretches between the four edges.
Similarly if we consider a Cube it has 8 vertices, 12 edges and 6 faces. These details of the plane and cube are shown in the image below:
An UVSphere in edit mode would like this:
Thus we may conclude that all objects are constructed using vertices,edges and faces. The same process is used for making both simple mesh like a cube or to construct more complex shapes which may go up to construct a human body shape or a complex machine part like a bolt, a gear wheel.
A bolt in mesh mode is shown below:
WORKING IN EDIT MODE
To work in edit mode, first open a 3D window in Blender, and add an object like a Cube.Hit Tab key go to edit mode.In edit mode you will see all the vertices,edges and faces. When these vertices,edges and faces are not selected they would appear in black colour. Hit "A" key to select all. Now you will see all the vertices,edges and faces in yellow colour.
You can toggle "A" key to select/deselect all objects in the 3D window.
In edit mode we can work with vertices, edges and faces in a detailed manner to design any desired shape. A number of tools are available to work in edit mode.
Look at the image below which shows the horizontal panel in edit mode. To the right of the button marked "Global" you will see four square buttons. The first one has a point(vertex) in orange colour, clicking on this enables vertex-select mode. The second button has a vertical line(edge) in orange colour,clicking on which will enable edge select mode, similarly the third button is used to enable face select mode. The fourth button shows four vertices and edges in the foreground and four vertices in the background. This button,when clicked on, enables selection of vertices in both foreground and background.
Another way to select a particular set of vertices and edges is to use the Box or Circle mode, which is activated by pressing "B" or "C" key. This method is explained earlier under the sub-head "SELECTING OBJECTS".
Once one or more vertex/edge are selected we can delete them,move(translate) them or extrude them or rotate them to create a modified mesh.
After we finish our work in edit mode the modified mesh can be seen as an object in the object mode(Press Tab key).
TOOL PANEL
Both in object mode and edit mode the Tool panel can be activated by pressing "T" key with the cursor within the 3D window. The Tool panel will be positioned along the left side of the 3D window. Different operations like translate, rotate, extrude and delete can be applied to the object selected in either mode. Side tab with label "Tools", "Create", "Relations, "Animation" are also shown.You may explore using these tools one by one.
NOTE: In Blender, it may be noted that there is always more than one way to do any operation like adding an object,editing, translating,rotating or scaling it.
