No one glue is suitable for all projects.
Wood- there are two main types of glue essential for woodworking, they are PVAs and Polyurethane. PVA is used for general purpose joints and comes in both interior and exterior varieties. Polyurethane is used for joints where stress will be on the joints as it has stronger bonding capabilities than PVA. An example would be glueing a chair leg back where it has broken off before.
Plastics - there are many different types of plastics and the type will determine what glue is suitable. Polypropylene and polyethylene plastics require a primer for good adhesion, which can be found in Loctite 2g And 4ml 2 Part All Plastic Superglue. It is also suitable for ABS plastics.
Porous materials- this encompasses a variety of different mediums but generally, a construction adhesive does a great job fixing most of them. It is suitable for bonding MDF, particleboard, timber, concrete, masonry, ceramics and most plastics.
All of these products come with sealing caps to easily store the products within their containers. - MitchellMc
I'm a huge fan of this glue. I laughingly glued back a broken corner piece on a concrete step thinking it would fall off with the first encounter of a person’s foot. Three years later, it's still there - and I can put my entire body weight (which is a lot!) on the corner - and it doesn't budge. - Noyade
A hot glue gun works well for working with items like small decorative stones, and you get a hot glue gun for about 10 bucks. You can also use 2-part epoxy glue, but I always find it messy and wasteful. - Benskimo
I sometimes use silicone in a tube for outside mosaic work and it has proven to be very successful over the years. Caulking guns are quite cheap, very practical to use and can be bought at Bunnings in a standard and also a mini size as well. - TerryN
Current choice of wood glue for me is Sikabond and for Melamine I want to try Titebond Melamine soon. - Brad
I am a big fan of Titebond. It has good shelf life. For general work where drying does not matter Titebond General, for food safe glue I use Ultimate III. I have just started using their liquid hide glue with no heating needed. That has a slow drying time. - r23on