The word texture means: what things are made of and how they feel.
Textures can be described as “rough”, “smooth”, “hard”, “soft”, “liquid”, “solid”, “lumpy”, “gritty” etc. The word “texture” is used for many different things. It can even be used in abstract senses, e.g. for music and poetry.
People like or dislike food because of its taste, but the texture of the food also plays a part in whether we like it or not. We enjoy the feel of it in our mouth. Food can be hard, soft, lumpy, gritty (e.g. a cake made with ground rice). Adding some lettuce to a cheese sandwich will change the texture of the sandwich: it makes it more crunchy.
In architecture we often talk about “texture”. This can mean: the things that the buildings are made of. It can also mean: the general way it looks, e.g. whether everything is built close together or whether there is plenty of space. This is an abstract use of the word, because it compares the way we see things to the way things feel.
Painters talk about the texture of paintings. This can be seen clearly in pointillism which is a way of painting by using lots of little dots. This gives the painting a very interesting texture.
In music, we can talk about the texture of a piece of music. If there are a lot of notes being played at once, we could call this a “thick” texture. If there are just two or three notes being played so that every note can be heard clearly, we could call this a “thin” or “clear” texture. Music may have a “polyphonic” texture or a “chordal” texture. The word “texture”, this time, is being used to describe something we hear instead of something we feel.